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1921. Keck/LRIS confirmation of Coma membership
ID:
ivo://CDS.VizieR/J/ApJ/723/251
Title:
Keck/LRIS confirmation of Coma membership
Short Name:
J/ApJ/723/251
Date:
21 Oct 2021
Publisher:
CDS
Description:
Keck/LRIS multi-object spectroscopy has been carried out on 140 of some of the lowest and highest surface brightness faint (19<R<22) dwarf galaxy candidates in the core region of the Coma Cluster. These spectra are used to measure redshifts and establish membership for these faint dwarf populations. The primary goal of the low surface brightness sample is to test our ability to use morphological and surface brightness criteria to distinguish between Coma Cluster members and background galaxies using high resolution Hubble Space Telescope/Advanced Camera for Surveys images. Candidates were rated as expected members, uncertain, or expected background. From 93 spectra, 51 dwarf galaxy members and 20 background galaxies are identified. Our morphological membership estimation success rate is ~100% for objects expected to be members and better than ~90% for galaxies expected to be in the background. We confirm that low surface brightness is a very good indicator of cluster membership. High surface brightness galaxies are almost always background with confusion arising only from the cases of the rare compact elliptical (cE) galaxies. The more problematic cases occur at intermediate surface brightness. Many of these galaxies are given uncertain membership ratings, and these were found to be members about half of the time. In a sample of 47 high surface brightness, ultracompact dwarf candidates, 19 objects have redshifts which place them in the Coma Cluster, while another 6 have questionable redshift measurements but may also prove to be members.
1922. Keck Lyman continuum spectroscopic survey (KLCS)
ID:
ivo://CDS.VizieR/J/ApJ/869/123
Title:
Keck Lyman continuum spectroscopic survey (KLCS)
Short Name:
J/ApJ/869/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of a deep spectroscopic survey quantifying the statistics of the escape of ionizing radiation from star-forming galaxies at z~3. We measure the ratio of ionizing to non-ionizing UV flux density <f_900_/f_1500_>_obs_, where f_900_ is the mean flux density evaluated over the range [880,910]{AA}. We quantify the emergent ratio of ionizing to non-ionizing UV flux density by analyzing high signal-to-noise ratio composite spectra formed from subsamples with common observed properties and numbers sufficient to reduce the statistical uncertainty in the modeled IGM+CGM correction to obtain precise values of <f_900_/f_1500_>_out_, including a full-sample average <f_900_/f_1500>_out_=0.057{+/-}0.006. We show that <f_900_/f_1500_>_out_ increases monotonically with W_{lambda}_(Ly{alpha}), inducing an inverse correlation with UV luminosity as a by-product. We fit the composite spectra using stellar spectral synthesis together with models of the ISM in which a fraction f_c_ of the stellar continuum is covered by gas with column density N_HI_. We show that the composite spectra simultaneously constrain the intrinsic properties of the stars (L_900_/L_1500_)_int_ along with f_c_, N_HI_, E(B-V), and f_esc,abs_, the absolute escape fraction of ionizing photons. We find a sample-averaged f_esc,abs_=0.09{+/-}0.01, with subsamples falling along a linear relation <f_esc,abs_>~0.75[W_{lambda}_(Ly{alpha})/110{AA}]. Using the far-UV luminosity function, the distribution function n(W(Ly{alpha})), and the relationship between W_{lambda}_(Ly{alpha}) and <f_900_/f_1500_>_out_, we estimate the total ionizing emissivity of z~3 star-forming galaxies with M_uv_<=-19.5, which exceeds the contribution of quasi-stellar objects by a factor of ~3, and accounts for ~50% of the total {epsilon}LyC at z~3 estimated using indirect methods.
1923. Keck/MOSFIRE spectroscopy of ZFOURGE galaxies
ID:
ivo://CDS.VizieR/J/ApJ/834/101
Title:
Keck/MOSFIRE spectroscopy of ZFOURGE galaxies
Short Name:
J/ApJ/834/101
Date:
21 Oct 2021
Publisher:
CDS
Description:
We compare galaxy scaling relations as a function of environment at z~2 with our ZFIRE survey where we have measured H{alpha} fluxes for 90 star-forming galaxies selected from a mass-limited (log(M_*_/M_{sun}_)>9) sample based on ZFOURGE. The cluster galaxies (37) are part of a confirmed system at z=2.095 and the field galaxies (53) are at 1.9<z<2.4; all are in the COSMOS legacy field. There is no statistical difference between H{alpha}-emitting cluster and field populations when comparing their star formation rate (SFR), stellar mass (M_*_), galaxy size (r_eff_), SFR surface density ({Sigma}(H{alpha}_star_)), and stellar age distributions. The only difference is that at fixed stellar mass, the H{alpha}-emitting cluster galaxies are log(r_eff_)~0.1 larger than in the field. Approximately 19% of the H{alpha} emitters in the cluster and 26% in the field are IR-luminous (L_IR_>2x10^11^L_{sun}_). Because the luminous IR galaxies in our combined sample are ~5 times more massive than the low-IR galaxies, their radii are ~70% larger. To track stellar growth, we separate galaxies into those that lie above, on, or below the H{alpha} star-forming main sequence (SFMS) using {Delta}SFR(M*)=+/-0.2dex. Galaxies above the SFMS (starbursts) tend to have higher H{alpha} SFR surface densities and younger light-weighted stellar ages than galaxies below the SFMS. Our results indicate that starbursts (+SFMS) in the cluster and field at z~2 are growing their stellar cores. Lastly, we compare to the (SFR-M*) relation from Rhapsody-G cluster simulations and find that the predicted slope is nominally consistent with the observations. However, the predicted cluster SFRs tend to be too low by a factor of ~2, which seems to be a common problem for simulations across environment.
1924. Keck spectroscopy of extragalactic HII regions
ID:
ivo://CDS.VizieR/J/ApJ/700/654
Title:
Keck spectroscopy of extragalactic HII regions
Short Name:
J/ApJ/700/654
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present very deep spectrophotometry of 14 bright extragalactic HII regions belonging to spiral, irregular, and blue compact galaxies. The data for 13 objects were taken with the High Resolution Echelle Spectrometer on the Keck I telescope. We have measured CII recombination lines in 10 of the objects and OII recombination lines in eight of them. We have determined electron temperatures from line ratios of several ions, especially those of low ionization potential.
1925. Kepler Data Search
ID:
ivo://archive.stsci.edu/kepler
Title:
Kepler Data Search
Short Name:
Kepler CS
Date:
22 Jul 2020 21:17:20
Publisher:
Space Telescope Science Institute Archive
Description:
Launched in 2009, the Kepler Mission is surveying a region of our galaxy to determine what fraction of stars in our galaxy have planets and measure the size distribution of those exoplanets. Although Kepler completed its primary mission to determine the fraction of stars that have planets in 2013, it is continuing the search, using a more limited survey mode, under the new name K2. This service is the main Kepler data search.
1926. Kepler Data Search
ID:
ivo://archive.stsci.edu/kepler_ktc
Title:
Kepler Data Search
Short Name:
KTC
Date:
22 Jul 2020 21:12:32
Publisher:
Space Telescope Science Institute Archive
Description:
This interface joins the Kepler Target Catalog (KTC) with other tables to allow users to access the Kepler data archive. Observed Kepler targets are included with their associated data set names. Since most of the Kepler light curve data is still proprietary, public data can be found by searching for release dates earlier than todays date.
1927. Kepler Input Catalog
ID:
ivo://archive.stsci.edu/kic10
Title:
Kepler Input Catalog
Short Name:
KIC
Date:
12 Feb 2020 19:43:29
Publisher:
Space Telescope Science Institute Archive
Description:
The KIC, or Kepler Input Catalog, is the primary source of information about objects observed as part of the ground-based Kepler Spectral Classification Program (SCP) in preparation for the selection of Kepler PI and GO targets. The KIC lists objects down to 21st magnitude, but it is not complete to this limit. Light from only about 1/3 of these 14 million objects falls on the Kepler CCD detector. A small number of the KIC objects are calibration objects distributed across the sky.
1928. Kepler K2 Data Search Catalog
ID:
ivo://archive.stsci.edu/k2
Title:
Kepler K2 Data Search Catalog
Short Name:
K2
Date:
22 Jul 2020 21:33:57
Publisher:
Space Telescope Science Institute Archive
Description:
Launched in 2009, the Kepler Mission is surveying a region of our galaxy to determine what fraction of stars in our galaxy have planets and measure the size distribution of those exoplanets. Although Kepler completed its primary mission to determine the fraction of stars that have planets in 2013, it is continuing the search, using a more limited survey mode, under the new name K2. The K2 Data Search Service provides the main catalog for all K2 data.
1929. Kepler K2 Ecliptic Plane Input Catalog
ID:
ivo://archive.stsci.edu/kepler/k2_epic
Title:
Kepler K2 Ecliptic Plane Input Catalog
Short Name:
K2 EPIC
Date:
12 Feb 2020 19:53:23
Publisher:
Space Telescope Science Institute Archive
Description:
Launched in 2009, the Kepler Mission is surveying a region of our galaxy to determine what fraction of stars in our galaxy have planets and measure the size distribution of those exoplanets. Although Kepler completed its primary mission to determine the fraction of stars that have planets in 2013, it is continuing the search, using a more limited survey mode, under the new name K2. The K2 Ecliptic Plane Input Catalog is the primary source of information about objects observed as potential targets for the K2 mission, as the Kepler Input Catalog was used for the original Kepler mission.
1930. Kepler Objects of Interest (KOI)
ID:
ivo://archive.stsci.edu/kepler_koi
Title:
Kepler Objects of Interest (KOI)
Short Name:
KOI CS
Date:
12 Feb 2020 19:51:12
Publisher:
Space Telescope Science Institute Archive
Description:
Launched in 2009, the Kepler Mission is surveying a region of our galaxy to determine what fraction of stars in our galaxy have planets and measure the size distribution of those exoplanets. Although Kepler completed its primary mission to determine the fraction of stars that have planets in 2013, it is continuing the search, using a more limited survey mode, under the new name K2. KOI is the Kepler Objects of Interest catalog listing observed Kepler targets which are flagged as potentially having exoplanets but may be false positives caused by other types of transient detection. This catalog is produced by the Kepler project and brought to MAST via NExScI.

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