- ID:
- ivo://CDS.VizieR/J/ApJ/900/9
- Title:
- AMIGA: The Circumgalactic Medium of Andromeda
- Short Name:
- J/ApJ/900/9
- Date:
- 14 Mar 2022 07:38:05
- Publisher:
- CDS
- Description:
- Project AMIGA (Absorption Maps In the Gas of Andromeda) is a survey of the circumgalactic medium (CGM) of Andromeda (M31, R_vir_~300kpc) along 43 QSO sightlines at impact parameters 25<~R<~569kpc (25 at R<~R_vir_). We use ultraviolet absorption measurements of SiII, SiIII, SiIV, CII, and CIV from the Hubble Space Telescope/Cosmic Origins Spectrograph and OVI from the Far Ultraviolet Spectroscopic Explorer to provide an unparalleled look at how the physical conditions and metals are distributed in the CGM of M31. We find that SiIII and OVI have a covering factor near unity for R<~1.2R_vir_ and <~1.9R_vir_, respectively, demonstrating that M31 has a very extended ~104-105.5K ionized CGM. The metal and baryon masses of the 104-105.5K CGM gas within R_vir_ are >~108 and >~4x1010 (Z/0.3Z{sun})-1M{sun}, respectively. There is not much azimuthal variation in the column densities or kinematics, but there is with R. The CGM gas at R<~0.5R_vir_ is more dynamic and has more complicated, multiphase structures than at larger radii, perhaps a result of more direct impact of galactic feedback in the inner regions of the CGM. Several absorbers are projected spatially and kinematically close to M31 dwarf satellites, but we show that those are unlikely to give rise to the observed absorption. Cosmological zoom simulations of ~L* galaxies have OVI extending well beyond R_vir_ as observed for M31 but do not reproduce well the radial column density profiles of the lower ions. However, some similar trends are also observed, such as the lower ions showing a larger dispersion in column density and stronger dependence on R than higher ions. Based on our findings, it is likely that the Milky Way has a ~104-105.5K CGM as extended as for M31 and their CGM (especially the warm-hot gas probed by OVI) are overlapping.
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- ID:
- ivo://CDS.VizieR/J/ApJS/95/1
- Title:
- Atlas of Quasar Energy Distributions
- Short Name:
- J/ApJS/95/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an atlas of the spectral energy distributions (SEDs) of normal, non-blazar, quasars over the whole available range (radio to 10 keV X-rays) of the electromagnetic spectrum. The primary (UVSX) sample includes 47 quasars for which the spectral energy distributions include X-ray spectral indices and UV data. Of these, 29 are radio quiet, and 18 are radio loud. The SEDs are presented both in figures and in tabular form, with additional tabular material published on CD-ROM. Previously unpublished observational data for a second set of quasars excluded from the primary sample are also tabulated. The effects of host galaxy starlight contamination and foreground extinction on the UVSX sample are considered and the sample is used to investigate the range of SED properties. Of course, the properties we derive are influenced strongly by the selection effects induced by quasar discovery techniques. We derive the mean energy distribution (MED) for radio-loud and radio-quiet objects and present the bolometric corrections derived from it. We note, however, that the dispersion about this mean is large (~one decade for both the infrared and ultraviolet components when the MED is normalized at the near-infrared inflection). At least part of the dispersion in the ultraviolet may be due to time variability, but this is unlikely to be important in the infrared. The existence of such a large dispersion indicates that the MED reflects only some of the properties of quasars and so should be used only with caution.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/24
- Title:
- A z=0 Multiwavelength Galaxy Synthesis (z0MGS). I.
- Short Name:
- J/ApJS/244/24
- Date:
- 14 Mar 2022 07:45:54
- Publisher:
- CDS
- Description:
- We present an atlas of ultraviolet and infrared images of ~15750 local (d<~50Mpc) galaxies, as observed by NASA's Wide-field Infrared Survey Explorer (WISE) and Galaxy Evolution Explorer (GALEX) missions. These maps have matched resolution (FWHM 7.5" and 15"), matched astrometry, and a common procedure for background removal. We demonstrate that they agree well with resolved intensity measurements and integrated photometry from previous surveys. This atlas represents the first part of a program (the z=0 Multiwavelength Galaxy Synthesis) to create a large, uniform database of resolved measurements of gas and dust in nearby galaxies. This atlas allows us estimate local and integrated star formation rates (SFRs) and stellar masses (M_*_) across the local galaxy population in a uniform way. In the appendix, we use the population synthesis fits of Salim+ (2016ApJS..227....2S and 2018ApJ...859...11S) to calibrate integrated M_*_ and SFR estimators based on GALEX and WISE. Because they leverage a Sloan Digital Sky Survey (SDSS)-based training set of >100000 galaxies, these calibrations have high precision and allow us to rigorously compare local galaxies to SDSS results. We provide these SFR and M_*_ estimates for all galaxies in our sample and show that our results yield a "main sequence" of star-forming galaxies comparable to previous work. We also show the distribution of intensities from resolved galaxies in NUV-to-WISE1 versus WISE1-to-WISE3 space, which captures much of the key physics accessed by these bands.
- ID:
- ivo://CDS.VizieR/J/ApJS/234/31
- Title:
- Carbon stars from LAMOST using machine learning
- Short Name:
- J/ApJS/234/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we present a catalog of 2651 carbon stars from the fourth Data Release (DR4) of the Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST). Using an efficient machine-learning algorithm, we find these stars from more than 7 million spectra. As a by-product, 17 carbon-enhanced metal- poor turnoff star candidates are also reported in this paper, and they are preliminarily identified by their atmospheric parameters. Except for 176 stars that could not be given spectral types, we classify the other 2475 carbon stars into five subtypes: 864 C-H, 226 C-R, 400 C-J, 266 C-N, and 719 barium stars based on a series of spectral features. Furthermore, we divide the C-J stars into three subtypes, C-J(H), C-J(R), and C-J(N), and about 90% of them are cool N-type stars as expected from previous literature. Besides spectroscopic classification, we also match these carbon stars to multiple broadband photometries. Using ultraviolet photometry data, we find that 25 carbon stars have FUV detections and that they are likely to be in binary systems with compact white dwarf companions.
- ID:
- ivo://mast.stsci/clash
- Title:
- Cluster Lensing And Supernova survey with Hubble (CLASH)
- Short Name:
- HST.CLASH
- Date:
- 22 Jul 2020 22:29:29
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- By observing 25 massive galaxy clusters with HST's new panchromatic imaging capabilities (Wide-field Camera 3, WFC3, and the Advanced Camera for Surveys, ACS), CLASH will accomplish its four primary science goals: - Map, with unprecedented accuracy, the distribution of dark matter in galaxy clusters using strong and weak gravitational lensing; - Detect Type Ia supernovae out to redshift z ~ 2, allowing us to test the constancy of dark energy's repulsive force over time and look for any evolutionary effects in the supernovae themselves; - Detect and characterize some of the most distant galaxies yet discovered at z > 7 (when the Universe was younger than 800 million years old - or less than 6% of its current age); - Study the internal structure and evolution of the galaxies in and behind these clusters.
- ID:
- ivo://mast.stsci/candels
- Title:
- Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS)
- Short Name:
- CANDELS
- Date:
- 12 Feb 2020 21:03:03
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- CANDELS is designed to document the first third of galactic evolution from z = 8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IR and ACS. It will also find the first Type Ia SNe beyond z greater than 1.5 and establish their accuracy as standard candles for cosmology. Five premier multi-wavelength sky regions are selected; each has multi-wavelength data from Spitzer and other facilities, and has extensive spectroscopy of the brighter galaxies. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to 109 solar masses out to z ~ 8.
- ID:
- ivo://CDS.VizieR/J/AJ/155/81
- Title:
- Diffuse X-ray-emitting gas in major mergers
- Short Name:
- J/AJ/155/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using archived data from the Chandra X-ray telescope, we have extracted the diffuse X-ray emission from 49 equal-mass interacting/merging galaxy pairs in a merger sequence, from widely separated pairs to merger remnants. After the removal of contributions from unresolved point sources, we compared the diffuse thermal X-ray luminosity from hot gas (L_X_(gas)) with the global star formation rate (SFR). After correction for absorption within the target galaxy, we do not see a strong trend of L_X_(gas)/SFR with the SFR or merger stage for galaxies with SFR>1 M_{sun}_/yr. For these galaxies, the median L_X_(gas)/SFR is 5.5x10^39^ ((erg/s)/M_{sun}_/yr), similar to that of normal spiral galaxies. These results suggest that stellar feedback in star-forming galaxies reaches an approximately steady-state condition, in which a relatively constant fraction of about 2% of the total energy output from supernovae and stellar winds is converted into X-ray flux. Three late-stage merger remnants with low SFRs and high K-band luminosities (L_K_) have enhanced L_X_(gas)/SFR; their UV/IR/optical colors suggest that they are post-starburst galaxies, perhaps in the process of becoming ellipticals. Systems with L_K_<10^10^ L_{sun}_ have lower L_X_(gas)/SFR ratios than the other galaxies in our sample, perhaps due to lower gravitational fields or lower metallicities. We see no relation between L_X_(gas)/SFR and Seyfert activity in this sample, suggesting that feedback from active galactic nuclei is not a major contributor to the hot gas in our sample galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/625/A49
- Title:
- Dimming event of RW Aurigae A
- Short Name:
- J/A+A/625/A49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- RW Aur A is a classical T Tauri star that has suddenly undergone three major dimming events since 2010. The reason for these dimming events is still not clear. The two epochs of observations uploaded here are on the deep dimming events (2015) and immediate after the dimmin event (2016).
- ID:
- ivo://CDS.VizieR/J/MNRAS/425/34
- Title:
- ExoMol line lists for BeH, MgH and CaH
- Short Name:
- J/MNRAS/425/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate line lists for three molecules, BeH, MgH and CaH, in their ground electronic states are presented. These line lists are suitable for temperatures relevant to exoplanetary atmospheres and cool stars (up to 2000K). A combination of empirical and ab initio methods is used. The rovibrational energy levels of BeH, MgH and CaH are computed using the programs Level and DPotFit in conjunction with 'spectroscopic' potential energy curves (PECs). The PEC of BeH is taken from the literature, while the PECs of CaH and MgH are generated by fitting to the experimental transition energy levels. Both spin-rotation interactions (except for BeH, for which it is negligible) and non-adiabatic corrections are explicitly taken into account. Accurate line intensities are generated using newly computed ab initio dipole moment curves for each molecule using high levels of theory. Full line lists of rotation-vibration transitions for ^9^BeH, ^24^MgH, ^25^MgH, ^26^MgH and ^40CaH are made available in an electronic form as supplementary data to this article and at www.exomol.com .
- ID:
- ivo://CDS.VizieR/J/MNRAS/440/1649
- Title:
- ExoMol line lists for CH4
- Short Name:
- J/MNRAS/440/1649
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new hot line list is calculated for ^12^CH_4_ in its ground electronic state. This line list, called 10to10, contains 9.8 billion transitions and should be complete for temperatures up to 1500K. It covers the wavelengths longer than 1{mu}m and includes all transitions to upper states with energies below hc 18000cm^-1^ and rotational excitation up to J=39. The line list is computed using the eigenvalues and eigenfunctions of CH_4_ obtained by variational solution of the SCHR equation for the rotation-vibration motion of nuclei employing program TROVE and a new 'spectroscopic' potential energy surface (PES) obtained by refining an ab initio PES (CCSD(T)-F12c/aug-cc-pVQZ) in a least-squares fitting to the experimentally derived energies with J=0, 1, 2, 3, 4 as extracted from the HITRAN database. The dipole transition probabilities are represented by the Einstein-A coefficients obtained using a previously reported ab initio dipole moment surface (CCSD(T)-F12c/aug-cc-pVTZ). Detailed comparisons with other available sources of methane transitions including HITRAN, experimental compilations and other theoretical line lists show that these sources lack transitions both higher temperatures and near infrared wavelengths. The 10to10 line list is suitable for modelling atmospheres of cool stars and exoplanets.