Data from the Kepler mission are housed in the Archive at the Space Telescope Science Institute (STScI) and accessed through MAST (Multi-mission Archive at Space Telescope). The Kepler Input Catalog (KIC), Kepler Target Catalog (KTC), Characterization Table (CT) and Kepler Results Catalog (KRC) are also accessed through MAST. Products such as light curves and target pixel data are stored on spinning disk. General information about Kepler may be found at the Kepler Mission http://www.kepler.arc.nasa.gov/ and the Kepler GO Program http://keplergo.arc.nasa.gov/ web sites.

1.1 Overview of Kepler

The Kepler mission is specifically designed to survey a region of the Milky Way galaxy to detect and characterize hundreds of Earth-size and smaller planets in or near the habitable zone. The transit method of planetary detection is used. The expected lifetime of the mission is 3.5 to 6 years.

The Kepler telescope has a 0.95-meter aperture and a 105 deg² (about 12 degree diameter) field-of-view (FOV). It is pointed at and records data from the same group of stars for the duration of the mission. The single instrument on board, a photometer, is an array of 42 CCDs arranged in 21 modules of 2 CCDs each. Each CCD has 2 outputs. The half-maximum bandpass is 435 to 845 nm, with >1% relative spectral response as short as 420 nm and as long as 905 nm. Each 50x25 mm CCD has 2200x1024 pixels. The interval between reads of a given pixel of a CCD is the integration time, which is composed of a “selectable” exposure time and fixed readout time of 0.520 seconds. All pixels are read out for each integration, and temporally summed in the Science Data Accumulator (SDA). Mission and GO target lists determine which of those SDA summed pixels are read out of the SDA and transmitted to the Solid State Recorder for later downlink. On average 32 pixels are read out of the SDA per target. The long cadence data are summed into onboard memory for 30 minutes, (270 integrations) while the short cadence data are 1 minute sums (9 integrations). Downlinks are expected to occur on an approximate monthly basis.

NB: The “selectable” exposure time is not specifiable by users.

A star field near the galactic plane, centered on galactic coordinates l = 76.32°, b = +13.5° (RA=19h 22m 40s, Dec=+44° 30' 00'), is the “field.” Figure 1-1 shows the field with the Kepler FOV superimposed. The squares show the 5 square degree FOV of each of the 21 modules. The gaps between the modules are aligned so that about half of the 15 stars in the FOV brighter than m_v=6 fall in these gaps. The 42 CCDs cover a four-way symmetrical pattern on the sky such that the same stars stay visible during the mission, even after a quarterly 90° roll. In addition, the orientation of the rows and columns of each module location on the sky is preserved for all roll orientations. The center module is only 180 degree symmetric. The roll is necessary to keep the solar arrays oriented towards the Sun and the radiator pointed towards deep space.

Kepler is in an Earth-trailing heliocentric orbit with a period of 372.5 days. In this orbit the spacecraft slowly drifts away from the Earth and is at a distance of over 0.5 AU after 3.5 years. The orbit permits continuous pointing on a single region of the sky. Additional advantages are the very stable pointing attitude and the avoidance of high radiation dosage associated with an Earth orbit, but from time to time the spacecraft is subject to solar flares.

The data will be calibrated. Bias (dark level) and smear (the photometer has no shutter) will be removed and values converted to electrons detected per cadence. The Data Management Center (DMC) will sort the raw and calibrated pixel values by target into target pixel files, permitting users to perform their own photometry or other forms of analysis. Light curves for all the stars will be produced on a quarterly basis at NASA Ames Research Center (ARC). These calibrated light curves will be sent to the DMC for archiving. There may be a quarter year lag for processing between receipt of data from the spacecraft and archiving of the data at the DMC. Data retrieval is via MAST.

At launch, ~150,000 targets were reserved for the mission. After the first year of operation, a “down select” may occur. The down select is expected to reduce the number of mission targets to ~100,000. The archived data for the deselected targets will become public within about two months of the down select.

During the final 10 days of commissioning and 35 days before the first quarterly roll, all stars brighter than Kepler magnitude = 13.5 were observed. Approximately 20,000 stars from this 45 day period were identified as red giants and were subsequently dropped from the science team program starting with the June 19, 2009 observations.

Through MAST, users will be able to search for existing targets of potential interest, determine when specific observations will be available (consistent with proprietary restrictions) for access and retrieve data. The community may propose to monitor additional objects of any nature that are in the Kepler FOV, such as variable stars or active galactic nuclei. See the NASA/ROSES website

http://nspires.nasaprs.com/external/viewrepositorydocument/cmdocumentid=129170/Summary%20of%20Solicitation%20Amend29.pdf Appendix D.9 for details on allowed GO science. In general, proposals that duplicate the exoplanet Key Project study are not allowed. See the GO Program website, http://kepler.nasa.gov/sci/godap.html and http://kelpergo.arc.nasa.gov for details on the proposal cycle.

For technical information, see http://kepler.nasa.gov/ .

1.2 Overview of Data Flow

Data are dumped from the spacecraft (S/C) through the Deep Space Network (DSN). They are received by the Mission Operations Center (MOC) at LASP where telemetry packets are binned into files by data type. The data are then sent to the Data Management Center (DMC) at STScI, where they are archived. The data are then decompressed, sorted by cadence (long or short) and pixel type (target, background or collateral), and converted to FITS. The keyword values are populated. At this point in processing, the data are termed to be “original.” The data are then sent to the Science Operations Center (SOC) at NASA Ames, where detailed calibration is performed and light curves are produced. The data are then returned to the DMC for archiving. The target pixel data are produced at the DMC from the returned data, and archived along with the light curves. The total time for one cycle (data dump from the S/C through archiving of the target pixel data) can be 3 to 6 months. For a given target, archive users can access the original and calibrated pixel values in the target pixel files or the integrated flux values in the light curves.

1.3 Overview of MAST

The Multi-mission Archive at STScI supports a variety of astronomical data archives, with the primary focus on scientifically related data sets in the optical, ultraviolet, and near-infrared parts of the spectrum. See http://archive.stsci.edu/missions.html for a full list of the missions hosted by MAST and http://archive.stsci.edu/hlsp/index.html for the high level science products, surveys, and catalog data distributed by MAST. MAST is a component of NASA's distributed Space Science Data Services (SSDS).

The staff of the Archive Sciences Branch and the Multi-mission Archive at STScI (MAST) provides:

world-wide technical and scientific leadership in archive system design
secure storage and reliable retrieval services for data from HST and all MAST-supported missions
user-friendly and scientifically useful search and cross-correlation tools
development and support for inter-archive communication and data transfer standards
accurate and useful mission archive documentation
helpful user support services with a 1 business day response time

MAST archives a variety of spectral and image data with a range of data characteristics. MAST provides a large suite of searches, including customized searches for each mission. It also provides several cross-mission search tools.

MAST also archives sets of community contributed High-Level Science Products (HLSPs). Users may search for HLSPs by target or coordinates by using the HLSP search page. MAST actively solicits submission of High-Level Science Products related to our missions and we provide guidelines for contributing them to MAST.

The MAST Users Group provides essential user perspectives on archive operations and development, including suggesting priorities for short and long term operational and scientific enhancements to the archive.

User feedback is obtained via an annual survey. Send an e-mail to archive@stsci.edu to participate in the next survey.

The archive website, http://archive.stsci.edu , is the best place to start learning about MAST and what it can do to enable your research. The web site should always be consulted for the most current information.

1.4 Related Documents

A reference description of Kepler may be found in the Kepler Instrument Handbook (KIH). The KIH describes the design, performance, and operational constraints of the Kepler hardware, and gives an overview of the pixel data sets available. A description of Kepler calibration may be found in the Kepler Data Analysis Handbook (KDAH). It is expected that both KIH and KDAH will be downloadable from MAST at a future time.

1.5 User Support Services

Archive Hotseat

Help or answers to any questions about archive issues may be obtained by sending e-mail to archive@stsci.edu, or by telephoning (410) 338-4547 Monday through Friday, 9 a.m. to 5 p.m. Eastern time.

The helpdesk staff will respond to questions concerning the archive and archive databases, and CDs, DVDs and hard disks provided by STScI. Helpdesk personnel also authorize accounts so that PIs and GOs can access their proprietary data. They will also provide advice concerning basic search strategies, and will investigate and document all problem reports. The archive helpdesk staff may not always know how to solve a problem, but they are responsible for finding out who does know the answer and for continuing to work with you until the problem is resolved. All initial communication from the user community to the archive should be directed to the archive helpdesk.

Questions and Comments

Communication regarding all aspects of the archive should normally be directed to the archive helpdesk (e-mail: archive@stsci.edu, or telephone (410) 338-4547). This will allow Archive staff to respond to your requests even when individual members of the group are away. If you feel your needs are not being adequately addressed through the helpdesk, place a message in the Suggestion Box located at http://archive.stsci.edu/suggestions.html

1.6 Registering as a User

Nomenclature: In this manual the term PI refers to the Kepler Project PI. GO refers to the lead investigator on any proposal submitted to the Kepler GO Program. Co-I refers to all other investigators on the Kepler Project and any additional investigators on any GO proposals.

Registration is not required to search the archive and retrieve public data. Registration and authorization is required to retrieve proprietary data, even for the Kepler Principal Investigator (PI) and Guest Observers (GO). An anonymous user has full access to the archive catalog. However, only registered and authorized users can retrieve proprietary data. You can register as an archive user by using the on-line form at http://archive.stsci.edu/registration. Alternatively, you can send e-mail to archive@stsci.edu. Within two working days of the receipt of your e-mail, you will be notified by e-mail of your registration as an archive user and will be provided with a username and a password. Note: The password can be changed from the registration page.

The PI and GOs can retrieve their proprietary data from the archive. To do so, they must be registered and authorized users (see above). The PI and GOs should request authorization for themselves when they register for their account. Only the PI and GOs may authorize anyone to access their data. If a Co-I wishes access to their data, they must have the PI or GO on the proposal send e-mail to archive@stsci.edu stating the proposal ID number and the identities of anyone who should be able to retrieve the data.

1.7 Proprietary Data Periods

To minimize the likelihood of false planet claims, the Kepler science team will have exclusive access to the data for enough time to perform follow-up ground-based observations for one year on a data stream twice as long as is being made available to the public. This period allows the team time to obtain follow-up observations for at least 3 transits by the time the data for 2 transits are released, assuming the planet’s orbital period is 1 year or less. Table 1-1 lists the data release time for the Key Program data, in months from the start of science data collection for the Mission, for data taken during through the specified quarter. Not all quarters are listed. A quarter is 3 months long. For example, data from the first quarter of operation will not be publicly released until 1 year (15 months – 3 months) after the end of science data collection for the first quarter.

Upon receipt of the quarterly calibrated data and light curves from the SOC, the DMC will generate the target pixel data for all targets. GOs will be notified of the availability of their data by the GO Office. It is the responsibility of the GOs to fetch their data from the archive. Unlike Kepler Key Program data, GO data will have a public release date set to one year from the time the light curves are archived. The DMC will notify the Kepler GO Office when GO data are archived. The GO Office will notify the GOs that their data are available. It is the responsibility of the GOs to retrieve their data.

Archived data for mission targets dropped from the planetary search program will generally be made public within 2 months after being dropped from the target list.

Table 1-1 – Data Release Timeline for Key Program

Quarter	Data release time*
1	15
2	27
3 and 4	39
5 and 6	51
7 and 8	63
9 and 10	75
All data	84

*Units are months from start of science data collection for the Mission.

All data are public one year after the end of data acquisition from the mission. Assuming a six year mission, all data should be public seven years from the start of science data collection.

Several types of Kepler data are non-proprietary. These are the collateral and background pixels files, the full frame images (FFIs) and the Kepler catalogs. The catalogs include the Kepler Input Catalog (KIC), the Characteristics Table (CT), the Kepler Target Catalog (KTC), and the Kepler Results Catalog (KRC). The catalogs contain metadata that will be staged through the Kepler archive interface at MAST. Information staged in these catalogs through MAST is public. As of this writing, the KTC and KRC are not yet available.

1.8 Finding Documentation

Documentation is available on-line for all archive holdings. The main archive page, http://archive.stsci.edu , provides links to a MAST tutorial, a general introduction to MAST and a "getting started" page. Each mission page has links to mission specific information (About ...), a mission specific "getting started" page and the MAST tutorial. MAST Kepler pages are at http://archive.stsci.edu/kepler/ . Other useful links for Kepler are http://kepler.nasa.gov/ , http://www.kepler.arc.nasa.gov/ and http://keplergo.arc.nasa.gov/ .

1.9 Getting Your Data

GOs on Kepler proposals and their authorized Co-Is may retrieve their data via the MAST Kepler Data Search and Retrieval form http://archive.stsci.edu/kepler/search.php . Entering the proposal id in the Proposal_id field and clicking on the Search button will return a list of the data in the archive for that proposal. Select the data to retrieve by clicking on the boxes in the Mark column. Note: there is a Mark All box. Click on the Submit button. The Retrieval Options page will be displayed. Fill out the required information then click on the Submit button. E-mail will be sent acknowledging receipt of the retrieval request. A second e-mail will be sent when the data have been retrieved. If the data were retrieved to the staging disk, follow the directions in the e-mail to copy the data from staging. The data will remain on staging for a limited time before being automatically deleted. See Chapter 3 for more details on the MAST Kepler search forms.

1.10 Publication Acknowledgement

Publications based on Kepler data retrieved from MAST should carry the following acknowledgment, which is in addition to any acknowledgement required by the Kepler project.

"Some/all of the data presented in this paper were obtained from the Multimission Archive at the Space Telescope Science Institute (MAST). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NAG5-7584 and by other grants and contracts.”

See the MAST Data Use Policy http://archive.stsci.edu/data_use.html for the current MAST grant number.

Chapter 2 Kepler Data Products

Many different files and products are archived for Kepler. These include, but are not limited to, light curves, target pixel data, focal plane characterization files (aka reference files), calibrated cadence data, which contain the pixel values from the spacecraft and the flux calibrated values, and background and collateral pixel files. Some products are available to GOs, others are available only to the Kepler Project PI and team members until the mission proprietary period has expired and still others are relevant only to the DMC as they are used to recreate data that have been corrupted or lost.

2.1 Definitions

The nomenclature for Kepler data can be a bit confusing. The following definitions are provided to help the reader distinguish among the variety of products.

File: For Kepler archival users, a file is in FITS format or ASCII text. See http://fits.gsfc.nasa.gov/ for the current FITS standard.

File name: The name a file has as it appears on disk or in the database. See section 2.2 for details.

Data set: A group of one or more files that are related to each other. For example, a data set may consist of the calibrated cadence data, the corresponding collateral data and the processing history file. The files in a data set are archived as a group. A data set may consist of a single file.

Data set name: The archive name for a group of one or more files that are archived as a group. Retrieval of a data set will result in retrieval of all files in the group.

Cadence: A cadence is the frequency with which summed data are read out of the SDA. Short cadence is a 1-minute sum while long cadence is a 30-minute sum. As pixels for every target are read out in each detector read, every “cadence file” includes pixel values for every target in the active target table at that time.

Cadence Data: In a general sense, cadence data are the temporal sum of pixel values read from the detector. In the strictest sense, cadence data consist of the original pixel values and the calibrated pixel values, for all targets, packaged in the same file. The file is called the calibrated cadence data and it is what is placed in the archive. In this document, unless otherwise noted, cadence data refers to the calibrated cadence data returned from the SOC.

Cadence Data Set: The cadence data for all the targets and collateral pixels, the background data, the cosmic ray correction tables and the history files make up the cadence data set. NB: All targets are contained in the same file. Most users will have no need for the cadence data set. NB: Because each cadence data set contains pixel values for all targets, the cadence data will follow the proprietary data release timeline shown in Table 1-1. See below for more details.

Target Pixel Data: After the flux calibrated cadence data are returned to the DMC, the individual target, background and collateral pixels are copied to separate target, background and collateral data files for each target. These target-based data are then archived. NB: Do not confuse the target pixel data, which is produced from the calibrated cadence data, with the cadence data.

Light Curve: For each target, the SOC provides two flux calibrated light curves for each quarter, using two different techniques. The techniques are optimal aperture photometry (OAP) and difference image analysis (DIA). Both light curves are contained within a single FITS format file.

Focal Plane Characterization Model: A set of reference files describing the response of the detectors, produced by the SOC, and used by the SOC and DMC to calibrate the data. These files are non-proprietary.

Pixel Mapping Reference Files: Called PMRF files, these files provide the key to identifying which data values in a given cadence data set belong to which targets. These files are produced at the DMC from the quarter-specific target and aperture definitions provided by the SOC. The PMRF files are non-proprietary.

Full Frame Image: Called FFI, this is a full readout of every CCD pixel. An FFI is taken before and after each quarterly roll of the spacecraft. The FFI is formatted as a FITS image.

Mod/out: Short for module/output, mod/out indicates which CCD recorded the data and which read amplifier was used to read out the detector. The values for mod start at 2 and run through 24, omitting 5 and 21. (Modules 1, 5, 21 and 25 are the fine guidance sensors.) The values of output range from 1 to 4. Although not used in this document, the syntax for mod/out is m.o, where m is the module number and o is the output number. Mod/out ranges from 2.1, 2.2, .. 2.4, 3.1 .. through 24.4, omitting 5 and 21. For a given target, the mod/out will change on a quarterly basis. See Figure 2-1 for the module numbering.

Channel: The sequential numbering, from 1 through 84, of the mod/outs. See Figure 2.1 for the channel numbering.

A general archive user can request light curves and target pixel data, after they are public. A Guest Observer (GO) can request their proprietary light curves and target pixel data. The Kepler PI, and authorized members of the team, can request non-GO proprietary light curves and target pixel data, and calibrated cadence data sets. All users can request focal plane characterization files, pixel mapping reference files and FFIs.

NB: The Kepler Project PI and authorized team members can not retrieve GO data until the proprietary period for those data has expired.

file:///C:/DOCUME~1/FRAQUE~1/LOCALS~1/Temp/ccdlayout.jpg

Figure 2‑1 Modules and channels with column and row directions. Each square shows 2 CCDs. The bold number in the each square is the module number. The smaller numbers in the corners of each square are the channel numbers. In the lower part of the figure, the column (C) and row (R) directions are indicated.

2.2 File Name Syntax

Some 35 different file types are archived for Kepler. Many of these file types are for the telemetry or for input files to the DMC or SOC processing. Less than half are for products that are available to a general archive user. To prevent confusion in the ground system, a standard syntax is used for Kepler filenames.

Kepler filenames have 3 components.

· Rootname: Usually a timestamp, for some file types the rootname contains other identifiers such as the kepler_id or the module/output (mod/out) number. The rootname begins with the character string ‘kplr’ followed by a time stamp of the form yyyydddhhmmss (e.g., kplr<stop_time>), where ddd is the day of year. If kepler_id or mod/out is present in the rootname, it precedes the timestamp (e.g., kplr<kepler_id>_<stop_time>). See table 2-1 for a list of rootnames.

· Suffix: The suffix indicates the type of data in the file within the data set (short cadence light curve, target pixel background data, etc.) See table 2-1 for a list of suffixes.

· Extension: The extension indicates the format of data contained in the file to application software (fits, or txt)

These three components are concatenated as shown to form the file name. This is the name of the file on disk.

<rootname>_<suffix>.<extension>

In the archive, the data set name is the rootname.

Table 2-1: Rootnames and Suffixes for Kepler Filenames

Type of Data+	Rootname*	suffix
Calibrated Light Curves:
Long cadence calibrated light curves	<kepler_id>-<stop_time>	llc
Short cadence calibrated light curves	< kepler _id>-<stop_time>	slc
Target Pixel Data:
Target pixel data - long	< kepler _id>-<stop_time>	lpd-targ
Target pixel data – short	< kepler _id>-<stop_time>	spd-targ
Target pixel collateral data - long	<mod/out>-<stop_time>	lpd-col
Target pixel collateral data - short	< kepler _id>-<stop_time>	spd-col
Target pixel background data	<mod/out>-<stop_time>	lpd-bkg
Focal Plane Characterization Model:
Small scale flat	<yyyymmddhh>	ssflat
Large scale flat	<yyyymmddhh>	lsflat
Combined flat	<yyyymmddhh>	cflat
linearity	<yyyydddmmhh>	linearity
Read noise	<yyyydddmmhh>	read-noise
Pixel response function	<yyyydddmmhh>	prf
Gain table	<yyyydddmmhh>	gain
Hot/bad pixel list	<yyyydddmmhh>	bad-pixel
Focal plane geometry model	<yyyydddmmhh>	geometry
2-d black table	<yyyydddmmhh>	2d-black
LDE undershoot table	<yyyydddmmhh>	undershoot
Full Frame Image:
FFI original data	<stop_time>	ffi-orig
FFI calibrated data	<stop_time>	ffi-cal
Processing history	<stop_time>	ffi-history
FFI cosmic ray correction table	<stop_time>	ffi-crct
Pixel Mapping Reference Files:
Long cadence target pixel mapping table	<yyyydddhhmmss>-<Tdid> <Adid>	lcm
Short cadence target pixel mapping table	<yyyydddhhmmss>-<Tdid>-<Adid>	scm
Background pixel mapping table	<yyyydddhhmmss>-<Tdid>-<Adid>	bgm
Long cadence collateral pixel mapping table	<yyyydddhhmmss>-<Tdid>-<Adid>	lcc
Short cadence collateral pixel mapping table	<yyyydddhhmmss>-<Tdid>-<Adid>	scc
Calibrated Cadence Data Set:
LC target data	<stop_time>	lcs-targ
LC collateral data	<stop_time>	lcs-col
Background data	<stop_time>	lcs-bkg
LC processing history	<stop_time>	lcs-history
LC target cosmic ray correction table	<stop_time>	lcs-crct
LC collateral cosmic ray correction table	<stop_time>	lcs-crcc
SC target data	<stop_time>	scs-targ
SC collateral data	<stop_time>	scs-col
SC processing history	<stop_time>	scs-history
SC cosmic ray correction table	<stop_time>	scs-crct
SC collateral cosmic ray correction table	<stop_time>	scs-crcc

+ LC = long cadence, SC = short cadence

* All rootnames begin with kplr.

2.3 Types of Data in the Archive

The general user will usually be interested in the light curves and the target pixel data. Although the focal plane characterization model files and full frame images (FFI) are non-proprietary, they are not generally useful at the target level. A person intending to propose for Kepler time will be interested in the KIC, CT and KTC. These catalogs are discussed in Chapter 3.

FITS headers:

Kepler science data will use FITS format in order to comply with astronomical data standards. Data headers will use standard FITS keywords to formulate the data definition. In addition, Kepler data will attempt to comply with all FITS recommended keyword usage current at the time of header design. FITS headers for cadence science data are specified in Appendix A. The primary header will contain keywords inherited by all subsequent extensions. The primary header/data unit (HDU) will not contain a data array.

Each file that has the photometer as the data source, that is the calibrated cadence and FFI data, will contain 84 binary table extensions, one extension for each of the 84 CCD channels with independent World Coordinate System parameters. Primary header keywords will specify data processing inputs, data quality, observational modes (long cadence, short cadence, FFI), proposal information (GO, PI), etc.

Keyword values are populated as processing proceeds through the DMC and SOC.

2.3.1 Light Curves

Light curves are produced for each target. At any time, there will be some 100,000 – 150,000 long cadence targets and up to 512 short cadence targets being observed. Short cadence targets will also be observed at long cadence. (There is an indication from the Project that this may not strictly be true. Any deviation is expected to be rare.) Long cadence targets will be observed for at least a quarter and short cadence targets will be observed for one to three months. Most planetary targets will be observed for the life of the mission. In the case where a target is observed at both long and short cadence, there will be one long cadence light curve and three short cadence light curves for each quarter.

As shown in Table 2-1, light curves are expected to have file names like kplr<kepler_id>-<stop_time>, with a suffix of either llc (long cadence) or slc (short cadence), and a file name extension of fits. A request for a long cadence light curve, by default, will return both the long cadence light curve and any associated short cadence light curves. The short cadence light curves will be packaged as a tar file.

A light curve is time series data, that is, a series of data points in time. Each data point corresponds to a measurement from a long or short cadence. Long and short cadence data are not mixed in a given light curve. For each data point there are multiple flux values, which the SOC derives using optimal aperture photometry and difference image analysis, along with uncertainties for each flux value. The centroid position for the target and time of the data point are also included. At this writing, the time is not yet settled (Gilliland, June, 2009).

There will be a single light curve file per target object (up to 4 (1 long cadence and 3 short cadence) if the target has both long cadence and short cadence data) generated each quarter. The file will contain both the OAP and DIA derived light curves.

The light curves are packaged as FITS binary table files. The fields of the binary table, all of which are scalar, are briefly described below and are listed in Table 2-2. The FITS header is listed in Appendix A.1.

The following data values are given for each data point in a light curve:

· time of the data point

· for the optimal aperture photometry

- centroid position of the target and uncertainty

- raw flux value and uncertainty

- corrected un-filled flux value and uncertainty

- instrument magnitude flux value and uncertainty

· for the difference image analysis

- raw flux value and uncertainty

- corrected un-filled flux value and uncertainty

- instrument magnitude flux value and uncertainty

Table 2-2 – Light curve data table fields

Column Number	Field	Bytes	Description
1	time	4	Delta time from time series zero point (seconds)*
2	cad num	4	cadence number
Optimal Aperture Photometry (OAP)
3	row_cent	4	row pixel location
4	σ_row	4	row position error
5	column_cent	4	column pixel location
6	σ_column	4	column position error
7	raw flux	4	raw flux value
8	σ_raw	4	raw flux error
9	cal flux	4	corrected un-filled flux value
10	σ_cal	4	corrected un-filled flux error
11	ins flux	4	instrument magnitude flux value
12	σ_ins	4	instrument magnitude flux error
Difference Image Analysis (DIA)
13	raw flux	4	raw flux value
14	σ_raw	4	raw flux error
15	cal flux	4	corrected un-filled flux value
16	σ_cal	4	corrected un-filled flux error
17	ins flux	4	instrument magnitude flux value
18	σ_ins	4	instrument magnitude flux error

*Time in data table is referenced to a barycentric start time in the header. All times are in units of MHJD.

The instrument magnitude flux value provides an “Instrument magnitude flux time series” that is scaled to astronomically meaningful magnitudes as best they can be reconstructed.

2.3.2 Target Pixel Data

Target pixel data files are produced for each target from the calibrated cadence data returned from the SOC. These are not cadence data. Recall, cadence data contain pixels for all targets. Up to 5 different files are produced for each target. These consist of the long and short cadence pixel data for the target, the collateral pixels for the long and short cadences, and the background pixels. See Table 2-1 for the file name syntax and Appendix A.2 for the description of the FITS binary tables. The term mod/out, which is short for module/output, indicates which CCD recorded the data and which read amplifier was used to read out the detector.

Both original pixel values and calibrated flux values are in the target pixel data files. The original pixel value is the integer value as recorded on the spacecraft. The calibrated flux values are those provided by the SOC. On average there are 32 pixels per target. The original and flux calibrated values are listed for each pixel.

The target pixel data files are archived as a dataset. A request for the data will return all extensions that were archived with the dataset.

2.3.3 Focal Plane Characterization Model

There are several different calibration or reference files, which constitute the focal plane characterization model, that are used by the DMC and SOC in processing and calibrating the cadence and FFI data. Table 2-1 lists the filenames and Table 2-3 gives the file type. For the FITS files, the headers are listed in Appendix C. Although these files are non-proprietary, they are of limited use to the archive user because the calibrations are applied to the cadence data, not to the individual exposure or light curve.

Table 2-3 Focal Plane Characterization Model (FPCM)

Type of Data	extension	+type
Small scale flat	ssflat	FITS
Large scale flat	lsflat	FITS
Combined flat	cflat	FITS
gain	gain	ASCII
linearity	linearity	ASCII
Hot/bad pixel list	bad-pixel	ASCII
2-d black level	2d-black	FITS
Read noise	read-noise	ASCII
LDE undershoot	undershoot	ASCII
Focal plane geometry	geometry	ASCII
Pixel response function	prf	FITS

+ values delimited with | for ASCII files

Table 2-4 shows the calibration steps performed at the DMC and which FPCM file is used in the step.

Table 2‑4 – Focal Plane Characterization Model files used in DMC pipeline processing

Processing step	FPCM file used	Comment
World Coordinate System parameters	Focal plane geometry	Focal plane to sky coordinate conversion.
FFI 2-d black level correction	2-d black level	Subtract 2-d black level model values form pixel values.
FFI dynamic black level correction	N/A
FFI gain correction	Gain	Multiply pixel value by gain. Populate GAIN keyword value in science extension header.
FFI nonlinearity correction	Linearity	Multiply pixel value by linearity (evaluated at the value of uncorrected pixel).
FFI undershoot correction	LDE undershoot
FFI dark current correction	N/A	Subtract dark current
FFI smear correction	N/A	Subtract smear level
FFI flat field correction	Combined flat	Divide by effective flat field
Population of FFI images statistic keywords	Hot/bad pixel list
Population of READNOIS keyword value in science extension headers	Read noise

The small scale flat, large scale flat and pixel response function files are not directly used in pipeline processing. However, they are archived for potential use or analysis by archival researchers

Within each file is a “use after” time, indicating when the file is applicable. The “use after“ time is the time when this version of the file supersedes the previous version.

Bad Pixel Table

Bad pixel data is used to flag targets that contain bad pixels. The bad pixel list is a table containing all of the various types of anomalous pixels. Each bad pixel is assigned a type, as listed in Table 2-5, and a value. One purpose of the Bad Pixel Table is to provide the capability for archive users to improve the Kepler image data.

Table 2-5 – Bad Pixel types

Pixel type	Type identifier	Pixel value description	Pixel value units
BLOOMING_TYPE	"blooming"	blooming trail count above background level	e-/sec
CROSSTALK_TYPE	"crosstalk"	cross talk signal count above background flux	e-/sec
UNUSABLE_TYPE	"unusable"	flag indicating cause of unusability: 0=unknown, 1=pixel defect, 2=row defect, 3=column defect	integer flag
HOT_TYPE	“hot”	dark current above mean dark current	e-/sec
DEAD_TYPE	“dead”	pixel response relative to mean pixel response	value relative to 1
GHOST_TYPE	“ghost”	ghost flux above the background flux	e-/sec
SCATTERED_TYPE	"scattered"	scattered light flux above background flux	e-/sec

The hot/bad pixel file is a character separated text file, where a bar (“|”) is used to separate the fields. There are 7 fields per line. These fields are listed in Table 2-6. Each bad pixel has a separate line in the file. The modified Julian day is used to denote the time at which the model becomes applicable. MJD is repeated on each line, but in practice these start times are required to be the same for all lines.

Table 2-6 – Hot/bad Pixel Table file format

Contents	Description	Data Type
MJD	Modified Julian Day, start time for model use	ASCII text
Module	The module for this gain value (2-4,6-20,22-24)	ASCII text
Output	The output for this gain value (1-4)	ASCII text
CCD row	The pixel row number in accumulation memory coordinates	ASCII text
CCD column	The pixel column number	ASCII text
Type	The type of bad pixel, where type is one of the identifiers	ASCII text
Value	The value of the bad pixel. The units of the bad pixel value depend on the type	ASCII text

Note: Kepler CCD coordinates are defined with rows 0-1060 and columns 0-1131. The row and column numbers include the collateral pixel regions, that is, all pixels stored in “accumulation memory” on board the flight segment. Rows 20-1043 and columns 12-1111 contain the photosensitive pixels.

There is one file for the entire focal plane. The file name contains a version identifier of the form YYYYMMDDHH. YYYY is the four-digit year, MM is the month in the year, DD is the day of the month, HH is hours in the day (in Pacific Time). For example, the name for a file generated on November 1, 2008 at 8:45 AM PT would be kplr2008110108_bad-pixel.txt.

2.3.4 Full Frame Image:

A Full Frame Image (FFI) is produced by reading and recording every pixel in each of the 42 CCDs. These images, which are taken before and after each roll of the spacecraft, are used to confirm the proper orientation and placement of the detector on the sky. FFIs are non-proprietary and are expected to occur quarterly. A complete FFI dataset consists of 4 files, each with a filename like Kplr<stop_time>_suffix. Three of the files are the result of DMC processing and 1 is produced by the SOC. See Tables 2-1 and 2-7 for details on the file names and data set.

Full Frame Images were taken during commissioning and are planned to be taken at least every 90 days, during periods of spacecraft roll, to verify target positions and assess photometer health.

The DMC process generates the two FFI data files, one containing the original (uncalibrated) pixels (ffi-orig) and one containing the calibrated pixels (ffi-cal), and the processing log. Each of the data files contains 84 image extensions, one for each module/output. See Appendix D.1.2 for a li sting of the FFI data header. The FFI cosmic ray correction table, an ascii file, is produced by the SOC.

Table 2-7 – FFI Data set and files

Data type	File suffix	Format
FFI - original	ffi-orig	FITS image
FFI - calibrated	ffi-cal	FITS image
FFI cosmic ray correction table	ffi-crct	ASCII
FFI Processing history file	ffi-history	FITS table (binary)

Original data are formatted as 32 bit integers (I*4) to hold the 23 bit data values. Original pixel values are contained in FITS image extensions, one extension per module/output. The data are represented as 32-bit two's complement binary integers as indicated by the BITPIX = 32 keyword value in the FITS table extension header.

In the event of a gap in the cadence data, a data fill value of 0xFFFFFFFF is used for the missing pixels. For original data represented as 32-bit two's complement binary integers, the gap fill value from the cadence data will be replaced by -1 in the FFI data table.

Calibrated data will be formatted as 32 bit (R*4) floating-point numbers. Each calibrated pixel is 23 bits deep (uncompressed). In the event of a gap in the cadence data, the data fill value of 0xFFFFFFFF for the missing pixels will be propagated to the calibrated pixel value; there will be no calibration operations performed on fill pixels.

2.3.5 Calibrated Cadence Data

As received at the DMC, the cadence data contain pixels for all targets, as well as the background and collateral pixels. From the cadence data, the DMC produces 5 separate FITS files each of which contains one of the five types of photometer data present in the cadence telemetry: long cadence target data, short cadence target data, background data, long cadence collateral data, and short cadence collateral data. Processing history files for long and short cadence processing are also produced. These files, known as the original cadence data set, are transferred to the SOC, where the data are calibrated and the cosmic ray correction tables are produced. The SOC then returns what is called the calibrated cadence data set to the DMC for archiving. Original and calibrated cadence data will be stored as separate binary table columns in the same file. Table 2.8 lists the 11 files that comprise the calibrated cadence data set. Note that only targets observed at both short and long cadence will have the full set of files. The FITS headers are listed in Appendix D.

The cadence target data files are FITS binary tables with 84 extensions, one extension for each module/output. The data in the binary table are contained in three fields: one for the raw pixel value, one for the calibrated pixel value, and one for the calibration uncertainty. The raw pixel values are 32-bit integers and the calibrated pixel values and calibration uncertainty are 32-bit floating-point numbers. Note that targets will appear in different module/outputs in different seasons.

Table 2‑8: Calibrated Cadence Data files

Data type	Cadence	File suffix
Long cadence target data	30 min	lcs-targ
Long cadence collateral data	30 min	lcs-col
Background pixels	30 min	lcs-bkg
Long cadence cosmic ray correction table	30 min	lcs-crct
Long cadence collateral cosmic ray correction table	30 min	lcs-crcc
LC Processing history file	30 min	lcs-history
Short cadence target data	1 min	scs-targ
Short cadence collateral data	1 min	scs-col
Short cadence cosmic ray correction table	1 min	scs-crct
Short cadence collateral cosmic ray correction table	1 min	scs-crcc
SC Processing history file	30 x 1 min	scs-set-history

Notes on Table 2-8:

· Subtraction is performed on-board for short cadence readouts so that each file represents independent 1-minute integrations.

· There are no background pixels in the short cadence readouts.

· LC is long cadence and SC is short cadence.

Long and short cadence target data

Both the long and short cadence target data files will hold a table that contains raw and calibrated pixel values each stored in 32 bits. There will be 30 short cadence target data files and 1 long cadence target data file in the cadence data set.

Background data

The background data files have the same format as the long and short cadence target data files. Background pixels are only taken at long cadence with 4500 pixels in each of the 84 mod/outs.

Long cadence collateral data

For each module, the long cadence collateral data contains: 1070 black level pixels, 1100 masked pixels, and 1100 virtual smear pixels. All three types of collateral data are contained in a single file. Long cadence collateral data are defined in the spacecraft configuration parameters and thus have no corresponding target or aperture ids for inclusion in a pixel mapping reference file.

FITS header keywords describe the content of the long cadence collateral data files. They specify a sentinel value for the collateral pixel data type (black level, masked, virtual smear), a table row number for start of each collateral data type, and a number of pixels for each collateral data type. The long cadence collateral pixel definition may change over time, but such changes are expected to be infrequent if they occur at all.

Short cadence collateral data

Pixels selected for the short cadence collateral data are based on a projection of the target aperture onto the collateral pixel rows and columns. Hence, because of the relatively small number of targets per mod/out in short cadence data, not all collateral data in a channel are read out. Each target contains on average: 9 black pixels, 9 masked smear pixels, 9 virtual smear pixels, 1 black-masked pixel, and 1 black-smear pixel.

History files

History files provide a record of the steps, along with associated comments and warnings, taken during the processing of a long cadence, short cadence, or FFI data set. History files are ASCII files produced during data processing at the DMC and the SOC.

Cosmic Ray Correction Table

The CRCT file is in FITS format with 84 binary table extensions, one binary table extension for each module/output. The binary table extension contains the fields for each entry as listed in Table 2-9. The FITS header specification for the CRCT data is listed in Appendix B.

Table 2-9 – Data table fields for CRCT

data field	size (bytes)
position of pixel along a row (range: 0-1069)	2
position of pixel along a column (range: 0- 1131)	2
pixel correction value	4
target ID	4
aperture ID	4
total	16

The CRCT is generated at the SOC for each cadence and incorporated into the cadence data set. There is one CRCT for the long cadence pixel data, and for short cadence data there are 30 CRCTs. Hence, for a single long cadence there will be 31 CRCT files. Cosmic ray corrections for background pixels are included in the long cadence CRCT files.

Cosmic ray correction tables are also generated for the collateral pixels. Again, the Cosmic Ray Collateral Correct (CRCC) tables will be generated at the SOC for each cadence and incorporated into the cadence data set. There is one CRCC for the long cadence pixel data, and for short cadence data there are 30 CRCCs, for a total of 31 CRCC files per long cadence.

The pixel correction value in the CRCT data table lists the correction applied to the cosmic ray affected pixels. The cosmic ray corrected pixel values replace the calibrated pixel values in the pixel data file. A data user willing to accept the DMC and SOC pipeline generated cosmic ray correction could ignore the CRCT. The pixel data file will hold the original (uncalibrated) pixel value and the cosmic ray corrected, calibrated pixel value. A data user could recover the uncorrected pixel values by adding the correction value (delta) in the CRCT to the calibrated pixel value in the pixel data file.

2.3.6: Ancillary Engineering Data

Ancillary engineering data is a subset of the engineering telemetry incorporated into the science data set in order to support science data analysis. There is an ancillary engineering data file for each interval that corresponds to the long cadence timing. The ancillary engineering data is included as a file with each long cadence data set.

An ancillary engineering data file exists, even if there is no corresponding long cadence science data. In this case, the ancillary engineering file forms its own data set. Typically, the ancillary engineering data is incorporated into the corresponding original cadence or FFI data set. The ancillary engineering data header is specified in Appendix F. As of this writing, ancillary engineering data are non-proprietary.

2.3.7 Spacecraft Ephemeris

The ephemeris is available through the SPICE system at NAIF, NASA’s Solar System Exploration Ancillary Information Facility (http://naif.jpl.nasa.gov/naif/ ). The vast majority of Kepler data users will not need the ephemeris.

2.4 The Standard Kepler Dataset

For an archive user, the standard Kepler dataset is the light curves. Users may also consider requesting the target pixel data, although the light curves are expected to satisfy the needs of most researchers.

2.5 Times in Kepler Headers

There are several FITS keywords in the Kepler data headers that relate to time. A good rule of thumb is the times in the primary header will be UTC (geocentric), while the times in the extension headers will be barycentric dynamical time (TDB). It is expected that times related to processing, such as when the FITS file was created or when the processing was completed will be in UTC. Times related to the date in the FITS file will be in TDB.

NB: By definition, TDB includes a relativistic correction. This is a periodic term, which may be as large as 1.6 millseconds. The yearly average of the periodic term is zero (0). As of this writing, the relativistic correction is not included in any of the Kepler data.

As of this writing, Modified Julian Date (MJD) is a common unit for the time. We anticipate a change from MJD to Julian Date (JD).

As of this writing, the FITS headers for the light curves are undergoing a review process, with the intent of improving the header content.

Chapter 3 Searching the Archive for Kepler Data

Users can search for Kepler data in a multitude of ways. Common searches are based on position, time of observation, target name or kepler_id, but all catalog fields are searchable. MAST allows the upload of a file containing a list of up to 1000 kepler_id’s, coordinates and/or target names for which the user wants searches conducted. Cross correlation with catalogs may be allowed in the future. Please note kepler_id and target name are different identifiers. MAST makes this distinction so that users may enter, say, NGC 6791 or TrES-2, as the target name and the Resolver will return the coordinates. Existing Resolvers do not yet recognize kepler_id as a target name.

This chapter contains descriptions of the MAST Kepler Data Search and Retrieval form, the MAST Kepler Target Search form, and the Kepler Input Catalog (KIC), Characteristics Table (CT) and Kepler Target Catalog (KTC) as hosted by MAST. Users intending to propose for Kepler time should search the KIC for targets via the Kepler Target Search form. Users interested in existing data should use the Kepler Data Search & Retrieval Form to search the archive catalog for data of interest.

3.1 The Kepler Catalogs as Presented at MAST

As of this writing, the Kepler catalogs at MAST consist of the Kepler Input Catalog (KIC), the Kepler Input Catalog modified by the Characteristics Table (CT), which will be called the merged KIC, and the Kepler Target Catalog (KTC) with additional fields from the archive catalog. The Kepler Results Catalog (KRC) will be hosted at MAST, although no version or description of it is yet available.

The Kepler Input Catalog contains information on approximately 15 million sources, most of which are visible in or nearby the Kepler FOV. Each source has an identification number, called the kepler_id, and a position (RA and Dec). Additional fields may or may not have values for each source. Table 3-1 lists the fields in the merged KIC, along with a short description of the field. Fields added by MAST are flagged. See the MAST help files at http://archive.stsci.edu/kepler/kepler_input_catalog/help/columns.html for more details.

Here are some facts for the KIC and CT.

The full KIC contains 13,161,029 rows (objects)
The CT (and likewise the merged KIC) contains 6,569,466 rows (about half of the KIC total)
The number of merged KIC entries considered on CCD for at least one season is 4,412,616 (about a third of the KIC total)
The number of merged KIC entries on CCD every season is 4,382,449.

The Kepler Target Catalog (KTC) contains all objects observed or scheduled for observation by Kepler. At launch, there will be some 170,000 targets, or more, in the KTC. The KTC, which is updated on a quarterly basis, holds planned observation start and stop times for each target. The times are given in both Modified Julian Date (MJD) and standard date format (i.e., YYYY-MM-DD HH:MM:SS). Table 3-2 lists all columns of the KTC, including several from the archive. For a given object, the kepler_id is the same in both the KIC and the KTC. The counter, a MAST added field, should not be used as an id as it can change with each KTC update. For more details on the columns see the MAST help files at http://archive.stsci.edu/kepler/kepler_target_catalog/help/columns.html .

The Characteristics Table (CT) contains parameters indicating if a given kepler_id is observable (“on silicon” is the termed used by the Kepler Science Team) for each of the 4 seasons, as well as other characteristics. Note there are plans to add a “reserved target” field, which will indicate that a given object is reserved for the Kepler Key Project. The GO Office directs proposers to not select these objects as target. Not all sources in the KIC have values for all parameters. In fact, only about half of the KIC entries are ever “on silicon.” Table 3-3 lists the CT parameters. MAST does not provide a direct search capability for the CT. Instead, the CT fields have been included in the merged KIC, which contains only those objects that have entries in both the KIC and CT. The Kepler Target Search form is used to search the merged KIC. Information about the CT parameters is given in the MAST help files, http://archive.stsci.edu/kepler/kepler_fov/help/search_help.html .

The Kepler Results Table (KRT) contains results obtained for the mission targets. Initially the KRT will be empty, as results are not expected to be available until some years after mission start. The final KRT will not be received until at least 1 year after mission end. The format of the KRT has not yet been defined.

Table 3-1 Fields in the Merged Kepler Input Catalog (KIC) as Displayed by MAST

Column	Description
kepler_id	Kepler identification number
ra*	Right ascension of object in hours
dec	Declination of object in decimal degrees
pmra	Proper Motion in right ascension
pmdec	Proper Motion in declination
umag	U magnitude
gmag	G magnitude
rmag	R magnitude
imag	I magnitude
zmag	Z magnitude
gredmag	GRed magnitude
d51mag	D51 magnitude
jmag	2MASS J magnitude
hmag	2MASS H magnitude
kmag	2MASS K magnitude
kepmag	Kepler magnitude
2massid%	2Mass catalog ID
scpid	ID from the SCPKEY table
altid	ID from an alternate source
altsource	Source of alternate ID
Star/gal ID	Star/galaxy indicator.
blend	Is object a blend
variable	Is object variable
Availability flag	2= reserved to Project, 1 = observed not reserved, 0 = not observed, not reserved
teff	Derived effective temperature
logg	Derived surface gravity
metallicity	Derived metallicity (Fe/H)
E(B-V)	Derived excess reddening E(B-V)
A_v	Derived extinction Av
radius	Estimate stellar radius
cq	Catalog quality indicator
pq	Photometry quality indicator
aq	Astrophysics quality indicator
Catalog key	Link to CATKEY table
SCP key	Link SCPKEY table
parallex	Parallax in arcseconds
Gal Lon	Galactic longitude
Gal Lat	Galactic latitude
pmtotal	Proper motion in arcsec/year
g-r color	(G-R) color
j-k color	(J-K) color
g-k color	(G-K) color
degree_ra	Right Ascension in decimal degrees
*fov_flag	Is object in the Kepler FOV or in the KTC
+sky_group_id	The channel where the target falls in season 2. Values will range from 1 to 84.
+crowding	The fraction of light in the aperture due to the target star. 1 means all the light is from the target, 0 implies all background. 0.5 means half the light is due to the target.
+Channel_season_0	Integer channel number for season 0.
+Channel_season_1	Integer channel number for season 1.
+Channel_season_2	Integer channel number for season 2.
+Channel_season_3	Integer channel number for season 3.
+Column_season_0	Column number for season 0.
+Column_season_1	Column number for season 1.
+Column_season_2	Column number for season 2.
+Column_season_3	Column number for season 3.
+Module_season_0	Integer module number for season 0.
+Module_season_1	Integer module number for season 1.
+Module_season_2	Integer module number for season 2.
+Module_season_3	Integer module number for season 3.
+Output_season_0	Integer output number per module for season 0.
+Output_season_1	Integer output number per module for season 1.
+Output_season_2	Integer output number per module for season 2.
+Output_season_3	Integer output number per module for season 3.
+Row_season_0	Row number for season 0.
+Row_season_1	Row number for season 1.
+Row_season_2	Row number for season 2.
+Row_season_3	Row number for season 3.

* Field added/modified by MAST.

% Although the field name is 2Mass ID, the field does not contain the standard 2Mass ID. See the “User's Guide to the 2Mass All Sky Data Release,” for information on the pts_key/cntr field at the following link.

http://www.ipac.caltech.edu/2mass/releases/allsky/doc/explsup.html

+ Field taken from the Characteristics Table.

Column	Description
Kepler Id	Running Kepler ID number
+Dataset Name	Dataset name for the exposure
RA(J2000)	RA in decimal degrees
Dec(J2000)	Dec in decimal degrees
Target Type	Cadence – LC or SC
Target Category	Target category
Planned Observation Start Time (MJD)	Planned start time MJD
Planned Observation Stop Time (MJD)	Planned start time in MJD
*Planned Observations Start Time	Planned start time in standard date format
*Planned Observation Stop Time	Planned end time in standard date format
Actual Observation Start Time	Actual start time
Actual Observation End Time	Actual end time
*KTC Counter	Sequential id
+VTC End Time	Value from END_TIME keyword in FITS file
+Release Date	Date when data become public.

Table 3-2 Fields in the Kepler Target Catalog (KTC) as Displayed by MAST

+ Field taken from the archive.

* Field added by MAST

Table 3-3 Parameters in the CT

Column	Description	Values
Kepler ID	The kepler id	integer
Channel season 0	Integer channel number for season 0.	1-84
Channel season 1	Integer channel number for season 1.	1-84
Channel season 2	Integer channel number for season 2.	1-84
Channel season 3	Integer channel number for season 3.	1-84
Column season 0	Column number for season 0.	20 to1043
Column season 1	Column number for season 1.	-201 to 1111
Column season 2	Column number for season 2.	-225 to 1094
Column season 3	Column number for season 3.	-225 to 1094
Module season 0	Integer module number for season 0.	2-24
Module season 1	Integer module number for season 1.	2-24
Module season 2	Integer module number for season 2.	2-24
Module season 3	Integer module number for season 3.	2-24
Output season 0	Integer output number per module for season 0.	1-4
Output season 1	Integer output number per module for season 1.	1-4
Output season 2	Integer output number per module for season 2.	1-4
Output season 3	Integer output number per module for season 3.	1-4
Row season 0	Row number for season 0.	-225 to 1094
Row season 1	Row number for season 1.	-225 to 1094
Row season 2	Row number for season 2.	-225 to 1094
Row season 3	Row number for season 3.	-225 to 1094
Skygroup ID	The module/output where the target falls. Values will range from 1 to 84.	1-84
Crowding Value	The fraction of light in the aperture due to the target star. 1 means all the light is from the target, 0 implies all background. 0.5 means half the light is due to the target.	0 - 1
Availability flag	2 = observed, reserved to Project, 1 = observed, not reserved, 0 = not observed, not reserved	0,1,2

3.2 The MAST Search Forms

MAST provides separate forms for searching for targets to observe (ie., exploring the merged KIC) and for locating Kepler data in the archive. Each form serves a different purpose. Searches of the merged KIC are done in support of proposal preparation. Called Kepler Target Searches or Kepler FOV searches, these searches of the merged KIC are via MAST’s Kepler Target Search form, and are used to find targets to observe with Kepler or to find astronomical information about the targets. Searches of the archive for existing data are called Kepler Data Searches, are done using MAST’s Kepler Data Search and Retrieval form and are based on the archive catalog and the KTC. These searches are done to locate and retrieve data from the archive. The forms function in the same manner although the search fields are different as the underlying catalogs and database contain different information. The kepler_id is the same in both forms.

An additional MAST form is under development. The form will allow database searches for FFIs, calibrated cadence data and engineering telemetry.

MAST provides standard forms, that is, forms that look and operate the same from mission to mission. On the "standard form", the top section consists of a place to enter a target name or coordinates and a Resolver. If a

target name is entered, the coordinates will be resolved using SIMBAD or NED and these coordinates will be used in the search. The user can also choose the search radius (the default is to 0.02 arcmin). Note the Resolver uses a standard MAST hierarchy, whose order is NED, SIMBAD, etc. The user can select a Resolver from the pull down menu. One of the options is ‘Don’t Resolve.’

Note the "file upload form" link near the top right of the form. Clicking on the link brings up a version of the standard form that allows the upload of a user created file. The file must be an ASCII text file or table with one entry per line with one or more fields (e.g. RA and Dec) separated with one of the allowed delimiters. Searches are allowed on coordinates, target name or kepler_id. Other fields are allowed in the file, but are not searchable. Up to 5000 lines are allowed. Several coordinate formats and delimiters are allowed. Check the help for information. The name of the file is the name the file has on the user’s disk. A browse button is provided.

The middle section of the search page contains mission specific fields, which can be used to qualify the search. For Kepler, four user-specified fields are provided. The menu (down arrow) next to each of these fields contains a complete list of the table columns. Select the desired field to add it to the search form. For more information about each field click on the link "Field Descriptions". This brings up a page of all the available columns the database column name, the label, the data type, the valid values in that field, and additional notes where applicable.

The third section provides output options for the search results. On the left side is a list of columns that is displayed by default. Columns can be removed by highlighting that column and clicking on the remove button to the right. Columns are added by choosing columns from the select box below and clicking the add button to the left of the select box. Change the order by clicking on field in the output columns box and click on the up and down buttons to the right. Clicking on the reset button will restore the default output columns settings. The output can be sorted by up to three columns. Note the following behavior when a sort option is used. If the upload contains more than 200 entries, the order of entries from the uploaded file is maintained. If the upload file contains less than 200 entries, the order in theuploaded file is not preserved. A ‘null’ option is available if no sorting is desired. When the no sort option is specified, the results are returned in the order in which they are stored in the database and for Kepler, this means in order of kepler_id.

The output format can be specified from a menu. Formats include HTML, comma separated value text, Excel spread sheet, and VO table format. The HTML format will give access to useful links and retrieval options. Since the astrophysical fields in the KIC are not populated for every object, searches that direct the results to a output file should use the Excel Spreadsheet output, or one of the CVS outputs that uses a character (i.e., comma or semi-colon) as the delimiter. Use of a space delimited CVS format can result in non-interpretable results.

Output coordinates are displayed in sexagesimal by default, but decimal degrees or decimal hours can be specified. Click on the headings for additional help.

3.2.1 Kepler Target Searches

Figure 3.1 shows the Kepler Target Search form located at http://archive.stsci.edu/kepler/kepler_fov/search.php

The form allows searches based on kepler_id, position, target name and/or physical characteristics, where the available physical characteristics are those provided in the merged KIC. Note: since there are ~7 million objects in catalog searched by this form, it is not a good idea to submit an unqualified search. Indeed, such a search is likely to time out, with no results returned.

There are 3 fields on or available through the Kepler Target Search form, which are not listed in Table 3-1 or Table 3-3, above. These fields are calculated from KIC or CT fields that are given above.

Min. Distance from Edge: The user may enter a value in pixels. The output value is calculated from the row and column values for each season and restricts the search to targets at least this number of pixels from the detector edge.

Seasons Target on CCD: The user may enter a given season, all or accept the default of any to define when or how often a target is on silicon. The returned values for this field are determined from the various channel, output, module, row and column fields in the CT. The planned start date for each season is given in Table 3-4. The seasons are numbered from 0 to 3, with 0 corresponding to Summer.

Table 3-4 Planned Start Date for Seasons

Year	Spring	Summer	Winter	Fall
2009	May 12	Jun 18	Sep 17	Dec 17
2010	Mar 22	Jun 24	Sep 23	Dec 22
2011	Mar 28	Jun 27	Sep 29	Dec 29
2012	Apr 2	Jun 28

Contamination is 1 – Crowding, where the Crowding value is taken from the CT. Contamination is a floating point number between 0 and 1 representing the fraction of light in the aperture due to the target star. A value of 0 means all the light is from the target, 1 implies all background. 0.5 means half the light is due to the target. The user may enter a value for contamination or leave it unspecified. Contamination may be added via one of the user-specified field elements.

Figure 3‑1 MAST Kepler Target Search Form

Figure 3-1 shows the MAST Target Search Form, set up for search. The Contamination, Teff and Log G fields have values entered to qualify the search. Note the use of carets, < and >, to provide starting or ending values. Also note the input in the Log G field, 3.0..3.5, which specifies a range of values starting with 3.0 and ending with 3.5. A User-specified field, R_Mag, was used to allow the R magnitude of the search to be qualified. Finally, in the Output Columns box, a number of fields were removed to make the results more readable. This search was executed and the results are shown in Figure 3-2. More information on general usage of MAST search forms is provided in the on-line MAST tutorial, which is accessible via the (Help) link in the top right corner of form.

Figure 3‑2 Results of Target Search

The results in Figure 3-2 are in the default HTML form. Clicking on the column name at the top of a column will sort the input by that column. A second click will order the sort in the opposite direction. A click on the column name link at the bottom of the results will bring up a page that describes the column.

Other output forms are available and can be specified on the Search Form, see Figure 3-1, in the lower right. Consult the on-line tutorial for additional details.

3.2.2 Kepler Data Searches

Users wishing to search for and/or retrieve Kepler data should use the Data Search and Retrieval Form, which is available at http://archive.stsci.edu/kepler/search.php . The features of this form are similar to those of the Target Search Form and function in the same way. On-line help is available. The search for data is a search using information from the archive tables, the KIC and the KTC. As of this writing, this form is not quite in its final state.

Figure 3-3 shows the Data Search and Retrieval Form set up for a very simple search, with only the Kepler ID as a qualifier. The results of this search are shown in Figure 3-4.

In the Search Results Form, note the Mark column, which is used to indicate the data to retrieve. When it is highlighted in yellow, the data are proprietary. Recall, proprietary data may only be retrieved by the PI of the proposal for which the data were taken, and any authorized co-Is. See section 1.5. The release data column, at the far right, shows when these data become public. To send a retrieval Request for these data, click the Mark boxes or click on “Mark all”, as shown in Figure 3-5, then click on Submit marked data for retrieval from STDAS. This will open up the Retrieval Options page, as shown in Figure 3-6.

The Retrieval Options Form is used for retrieval of public and proprietary data, and for anonymous retrievals of public data. For proprietary data, the user must enter their archive account username and password. For public or non-proprietary data, an archive account may be used, or anonymous retrieval is available. Enter anonymous for the Archive Username and your e-mail for the Archive Password. For all requests, even anonymous, a valid e-mail account is necessary in order for the archive to send status information regarding the retrieval request.

Under Delivery options, indicate how the data should be delivered. I