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Hot Star Extension to the Hubble Space Telescope Stellar Spectral Library ("HOTSTARLIB")

Khan & Worthey et al. 2018, A&A, accepted

Introduction

Description of Data Products

Data Access

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Introduction

NGSL stars and our sample in a log Teff, log g diagram. NGSL stars (Koleva & Vazdekis 2012, A&A, 538, 143) are separated by abundance, [Fe/H] > -1 (red plus) or [Fe/H] < -1 (blue plus). Hot star library candidate stars are marked with circles. The circles are filled for stars that were observed and included in this HLSP. All O star candidates (blue) were observed, but not all PAGB stars (green) or He-burning stars (red). To guide the eye, an approximate Eddington stability line is drawn, and approximate spectral type boundaries. From Khan & Worthey et al. (2018).
We present 41 low resolution spectra of 40 stars from 0.2 micrometers (ultraviolet) to 1.0 micrometers (near infrared) with excellent fluxing. The stars include normal O-type stars, helium-burning stars, and post-asymptotic giant branch (PAGB) stars. Spectra were obtained with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) using three low resolution gratings, G230LB, G430L, and G750L. Cosmic ray hits and fringing in the red were corrected. A correction for scattered light was applied, significant only for our coolest stars. Cross-correlation was used to bring the spectra to a common, final, zero velocity wavelength scale. Finally, synthetic stellar spectra were used to estimate line of sight dust extinction to each star, and a five-parameter dust extinction model was fit, or a one-parameter fit in the case of low extinction. These spectra dovetail with the similar Next Generation Stellar Library (NGSL) spectra, extending the NGSL's coverage of stellar parameters, and extending to helium burning stars and stars that do not fuse. You can refer to the full collection of HOTSTARLIB data products in papers or webpages using the DOI http://dx.doi.org/10.17909/T9BH65.

Description of Data Products

Spectral FITS Files

Each spectrum is stored as a binary FITS file. The primary header contains metadata about the observations, as well as a rebinned, dust-corrected spectrum for the target. The first extension contains a ragged-lambda, dust-corrected spectrum of the target. The final extension contains a list of the original HST observation IDs used to construct the spectrum.

Primary HDU (HDU 0): Rebinned, Dust-Corrected Spectrum
Data stored in table (3,981 columns, 5 rows). Note wavelengths are in WCS. The rows are:
ARRAY #1 Dust-Corrected Flux
ARRAY #2 Dust-Corrected Flux Uncertainty
ARRAY #3 Raw Flux
ARRAY #4 Raw Flux Uncertainty
ARRAY #5 Extinction Curve
First Extension (HDU 1): Ragged-lambda, Dust-Corrected Spectrum
Data stored in table (6 columns, 2,908 to 2,910 rows). The columns are:
WAVELENGTH Wavelength (Angstroms)
FLUX_DUST_CORRECTED Dust-Corrected Flux
UNCERTAINTY_DUST_CORRECTED Dust-Corrected Flux Uncertainty
FLUX_UNCORRECTED Raw Flux (before correction)
UNCERTAINTY_UNCORRECTED Raw Flux Uncertainty (before correction)
EXTINCTION_CURVE Model Extinction Curve
Second Extension (HDU 2): HST ObsID List
Data stored in table (1 column, 12 rows). The rows are:
DATASET_LIST List of HST observation IDs used to make spectrum.

Data Access

The spectra can be downloaded using the table below.

Target RA Dec Lit. T_eff Lit. log(g) Download
BD+60D513 02:34:02.5285 +61:23:10.848 40000. 3.70 SPECTRUM
DR-AND 01:05:10.704 +34:13:06.32 6200. 2.30 SPECTRUM
EGB-5 08:11:12.768 +10:57:17.10 42000. 5.80 SPECTRUM
GJ-894.3 23:19:58.39814 -05:09:56.1604 40000. 5.00 SPECTRUM
GLMP-334 12:38:53.10 -57:56:31.9 7400. 1.40 SPECTRUM
HD107969 12:24:30.76 -18:47:05.4 82000. 5.50 SPECTRUM
HD15570 02:32:49.42013 +61:22:42.0956 49000. 3.51 SPECTRUM
HD164794 18:03:52.44466 -24:21:38.6269 47000. 3.90 SPECTRUM
HD168075 18:18:36.061 -13:47:36.51 49000. 3.95 SPECTRUM
HD192639 20:14:30.42806 +37:21:13.8107 38000. 3.37 SPECTRUM
HD205805 21:39:10.61355 -46:05:51.5321 25000. 5.00 SPECTRUM
HD207198 21:44:53.27923 +62:27:38.0479 34000. 3.31 SPECTRUM
HD210839 22:11:30.57571 +59:24:52.1546 40000. 3.50 SPECTRUM
HD217086 22:56:47.19030 +62:43:37.6487 40000. 3.71 SPECTRUM
HD228199 20:11:27.2625 +36:29:56.845 30000. 3.91 SPECTRUM
HD26847 04:14:15.782 -12:44:21.68 70000. 4.60 SPECTRUM
HD269696 05:31:40.3489 -69:53:02.183 40000. 5.50 SPECTRUM
HD46150 06:31:55.520 +04:56:34.28 46900. 3.85 SPECTRUM
HD46966 06:36:25.88773 +06:04:59.4769 38100. 3.89 SPECTRUM
HD93250 10:44:45.02626 -59:33:54.6841 51000. 3.90 SPECTRUM
HD93521 10:48:23.51137 +37:34:13.0922 33500. 3.95 SPECTRUM
HDE303308 10:45:05.848 -59:40:06.36 48000. 3.91 SPECTRUM
HEN-2-182 16:54:35.168 -64:14:28.44 36000. 3.40 SPECTRUM
IC2448 09:07:06.262 -69:56:30.57 55000. 4.50 SPECTRUM
LSIII+52D24 22:04:12.302 +53:04:01.37 24000. 3.00 SPECTRUM
LSIV-12D111 20:01:49.8373 -12:41:17.600 20500. 2.35 SPECTRUM
LSS-1362 09:52:44.524 -46:16:47.47 100000. 5.30 SPECTRUM
LSV+46D21 04:43:21.270 +46:42:05.84 83000. 6.70 SPECTRUM
NGC1535 04:14:15.782 -12:44:21.68 58000. 4.30 SPECTRUM
NGC2392 07:29:10.76590 +20:54:42.4830 47000. 3.60 SPECTRUM
NGC3242 10:24:46.107 -18:38:32.64 68000. 4.60 SPECTRUM
NGC6611-367 18:18:52.67456 -13:49:42.6158 35000. 4.15 SPECTRUM
NGC6853 19:59:36.379 +22:43:15.75 110000. 6.70 SPECTRUM
NGC7094 21:36:52.97 +12:47:19.0 110000. 5.70 SPECTRUM
PHL-382 22:43:06.0147 -14:50:37.393 18200. 4.10 SPECTRUM
PN-A66-78 21:35:29.38 +31:41:45.3 110000. 5.50 SPECTRUM
PN-K-1-16 18:21:52.111 +64:21:53.22 140000. 6.40 SPECTRUM
PN-TC-1 17:45:35.3020 -46:05:23.682 33000. 3.20 SPECTRUM
RX-CET 00:33:38.28188 -15:29:14.7888 6186. 2.00 SPECTRUM
RX-J0122.9-752117 01:22:53.37 -75:21:13.8 180000. 7.50 SPECTRUM
SB-707 01:43:48.54613 -24:05:10.2360 34000. 6.00 SPECTRUM