- ID:
- ivo://CDS.VizieR/J/ApJ/842/120
- Title:
- Large spectrosc. survey of Palomar 5 stellar stream
- Short Name:
- J/ApJ/842/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two spectroscopic surveys of the tidal stellar stream of the Palomar 5 globular cluster undertaken with the VLT/FLAMES and AAT/AAOmega instruments. We use these data in conjunction with photometric data presented in the previous contribution in this series to classify the survey stars in terms of their probability of belonging to the Palomar 5 stellar stream. We find that high-probability candidates are only found in a very narrow spatial interval surrounding the locus of the stream on the sky. PanSTARRS RRLyrae stars in this region of the sky are also distributed in a similar manner. The absence of significant "fanning" of this stellar stream confirms that Palomar 5 does not follow a chaotic orbit. Previous studies have found that Palomar 5 is largely devoid of low-mass stars, and we show that this is true also of the stellar populations along the trailing arm out to 6{deg}. Within this region, which contains 73% of the detected stars, the population is statistically identical to the core, implying that the ejection of the low-mass stars occurred before the formation of the stream. We also present an updated structural model fit to the bound remnant, which yields a total mass of 4297+/-98M_{sun}_ and a tidal radius 0.145+/-0.009kpc. We estimate the mass of the observed system including the stream to be 12200+/-400M_{sun}_, and the initial mass to have been ~47000+/-1500M_{sun}_.
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- ID:
- ivo://CDS.VizieR/J/A+A/587/A78
- Title:
- LARS VIII. Spatially resolved Halpha kinematics
- Short Name:
- J/A+A/587/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present integral field spectroscopic observations with the Potsdam Multi-Aperture Spectrophotometer of all 14 galaxies in the z~0.1 Lyman Alpha Reference Sample (LARS). We produce 2D line-of-sight velocity maps and velocity dispersion maps from the Balmer {alpha} (H{alpha}) emission in our data cubes. These maps trace the spectral and spatial properties of the LARS galaxies' intrinsic Ly{alpha} radiation field. We show our kinematic maps that are spatially registered onto the Hubble Space Telescope H{alpha} and Lyman{alpha} (Ly{alpha}) images. We can conjecture a causal connection between spatially resolved H{alpha} kinematics and Ly{alpha} photometry for individual galaxies. However, no general trend can be established for the whole sample. Furthermore, we compute the intrinsic velocity dispersion {sigma}_0_, the shearing velocity v_shear_, and the v_shear_/{sigma}_0_ ratio from our kinematic maps. In general LARS galaxies are characterised by high intrinsic velocity dispersions (54km/s median) and low shearing velocities (65km/s median). The v_shear_/{sigma}_0_ values range from 0.5 to 3.2 with an average of 1.5. It is noteworthy that five galaxies of the sample are dispersion-dominated systems with v_shear_/{sigma}_0_<1, and are thus kinematically similar to turbulent star-forming galaxies seen at high redshift. When linking our kinematical statistics to the global LARS Ly{alpha} properties, we find that dispersion-dominated systems show higher Ly{alpha} equivalent widths and higher Ly{alpha} escape fractions than systems with v_shear_/{sigma}_0_>1. Our result indicates that turbulence in actively star-forming systems is causally connected to interstellar medium conditions that favour an escape of Ly{alpha} radiation.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A10
- Title:
- LARS XI. Turbulence Driven Lyman Alpha Escape
- Short Name:
- J/A+A/644/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the global dust and (molecular) gas content in the Lyman Alpha Reference Sample (LARS), i.e. 14 local star-forming galaxies. We characterize their interstellar medium and relate newly derived properties to quantities relevant for Ly{alpha} escape. We observed LARS galaxies with Herschel/PACS, SOFIA/FIFI-LS, the IRAM 30m telescope and APEX, targeting far-infrared (FIR) continuum and emission lines of [CII]158um, [OI]63um, [OIII]88um and low-J CO lines. Using Bayesian methods we derive dust model parameters and estimate total gas masses for all LARS galaxies, taking into account a metallicity-dependent gas-to-dust ratio. Star formation rates were estimated from FIR, [CII]158um and [OI]63um luminosities. LARS covers a wide dynamic range in the derived properties, with FIR-based star formation rates from ~0.5-100M_{sun}/yr, gas fractions between ~15-80% and gas depletion times ranging from a few hundred Myr up to more than 10Gyr. The distribution of LARS galaxies in the {SIGMA}_gas_ vs. {SIGMA}_SFR_ (Kennicutt-Schmidt plane) is thus quite heterogeneous. However, we find that LARS galaxies with the longest gas depletion times, i.e. relatively high gas surface densities ({SIGMA}_gas_) and low star formation rate densities ({SIGMA}_SFR_ have by far the highest Ly{alpha} escape fraction. A strong [Math Processing Error]linear relation is found between Ly{alpha} escape fraction and the total gas (HI+H_2_) depletion time. We argue that the Ly{alpha} escape in those galaxies is driven by turbulence in the star-forming gas that shifts the Ly{alpha} photons out of resonance close to the places where they originate. We further report on an extreme [CII]158um excess in LARS 5, corresponding to ~14+/-3% of the FIR luminosity, i.e. the most extreme [CII]-to-FIR ratio observed in a non-AGN galaxy to date.
- ID:
- ivo://CDS.VizieR/J/A+A/425/489
- Title:
- Late-type stars in the inner Milky Way
- Short Name:
- J/A+A/425/489
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a narrow-band infrared imaging survey of a narrow strip (12' wide) around the Galactic equator between 6{deg} and 21{deg} of galactic longitude aimed at detecting field stars with strong CO absorption, mainly late-type giants and supergiants. Our observations include follow-up low resolution spectroscopy (R=980) of 191 selected candidates in the H and K bands.
1335. Late-type star spectra
- ID:
- ivo://CDS.VizieR/J/A+AS/123/473
- Title:
- Late-type star spectra
- Short Name:
- J/A+AS/123/473
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work we present spectroscopic observations centered in the spectral lines most widely used as optical indicators of chromospheric activity (H{alpha}, H{beta}, Ca II H & K, and He I D{3}) in a sample of F, G, K and M chromospherically inactive stars. The spectra have been obtained with the aim of providing a library of high and mid-resolution spectra to be used in the application of the spectral subtraction technique to obtain the active-chromosphere contribution to these lines in chromospherically active single and binary stars. This library can also be used for spectral classification purposes. A digital version with all the spectra is available via ftp and the World Wide Web (WWW) in both ASCII and FITS formats
- ID:
- ivo://CDS.VizieR/J/AJ/161/194
- Title:
- LCs and RVs of 5 exoplanets discovered by TESS
- Short Name:
- J/AJ/161/194
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We present the discovery and characterization of five hot and warm Jupiters TOI-628b (TIC281408474; HD288842), TOI-640b (TIC147977348), TOI-1333b (TIC395171208, BD+473521A), TOI-1478b (TIC409794137), and TOI-1601b (TIC139375960)-based on data from NASA's Transiting Exoplanet Survey Satellite (TESS). The five planets were identified from the full-frame images and were confirmed through a series of photometric and spectroscopic follow-up observations by the TESS Follow-up Observing Program Working Group. The planets are all Jovian size (R_P_=1.01-1.77R_J_) and have masses that range from 0.85 to 6.33M_J_. The host stars of these systems have F and G spectral types (5595<~Teff<~6460K) and are all relatively bright (9.5<V<10.8, 8.2<K<9.3), making them well suited for future detailed characterization efforts. Three of the systems in our sample (TOI-640b, TOI-1333b, and TOI-1601b) orbit subgiant host stars (logg<4.1). TOI-640b is one of only three known hot Jupiters to have a highly inflated radius (R_P_>1.7R_J_, possibly a result of its host star's evolution) and resides on an orbit with a period longer than 5days. TOI-628b is the most massive, hot Jupiter discovered to date by TESS with a measured mass of 6.31_-0.30_^+0.28^M_J_ and a statistically significant, nonzero orbital eccentricity of e=0.074_-0.022_^+0.021^. This planet would not have had enough time to circularize through tidal forces from our analysis, suggesting that it might be remnant eccentricity from its migration. The longest-period planet in this sample, TOI-1478b (P=10.18days), is a warm Jupiter in a circular orbit around a near-solar analog. NASA's TESS mission is continuing to increase the sample of well-characterized hot and warm Jupiters, complementing its primary mission goals.
- ID:
- ivo://CDS.VizieR/J/ApJ/836/14
- Title:
- LCs & spectra of SDSS J1515+1511 lens system
- Short Name:
- J/ApJ/836/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze new optical observations of the gravitational lens system SDSS J1515+1511. These include a 2.6-year photometric monitoring with the Liverpool Telescope (LT) in the r band, as well as a spectroscopic follow-up with the LT and the Gran Telescopio Canarias (GTC). Our r-band LT light curves cover a quiescent microlensing period of the doubly imaged quasar at z_s_=2.049, which permits us to robustly estimate the time delay between the two images A and B: 211+/-5d (1{sigma} confidence interval; A is leading). Unfortunately, the main lensing galaxy (G1) is so faint and close to the bright quasar that it is not feasible to accurately extract its spectrum through the GTC data. However, assuming the putative redshift z_G1_=0.742, the GTC and LT spectra of the distant quasar are used to discuss the macrolens magnification, and the extinction and microlensing effects in G1. The new constraints on the time delay and macrolens magnification ratio essentially do not change previous findings on the mass scale of G1 and external shear, while the redshift of the lensing mass is found to be consistent with the assumed value of z_G1_. This is clear evidence that G1 is indeed located at z_G1_=0.742. From the GTC data, we also obtain the redshift of two additional objects (the secondary galaxy G2 and a new absorption system) and discuss their possible roles in the lens scenario.
- ID:
- ivo://CDS.VizieR/J/MNRAS/244/408
- Title:
- LDSS Deep Redshift Survey
- Short Name:
- J/MNRAS/244/408
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using a multisplit spectrograph, LDSS, we have obtained intermediate dispersion spectroscopy for a new sample of 149 faint objects selected randomly from the magnitude range 21<=bJ<=22.5 in three high-latitude fields.
- ID:
- ivo://CDS.VizieR/J/ApJS/239/27
- Title:
- LEGA-C DR2: galaxies in the COSMOS field
- Short Name:
- J/ApJS/239/27
- Date:
- 01 Mar 2022
- Publisher:
- CDS
- Description:
- We present the second data release of the Large Early Galaxy Astrophysics Census (LEGA-C), an ESO 130-night public spectroscopic survey conducted with VIMOS on the Very Large Telescope. We release 1988 spectra with typical continuum S/N~20{AA}^-1^ of galaxies at 0.6<~z<~1.0, each observed for ~20hr and fully reduced with a custom-built pipeline. We also release a catalog with spectroscopic redshifts, emission-line fluxes, Lick/IDS indices, and observed stellar and gas velocity dispersions that are spatially integrated quantities, including both rotational motions and genuine dispersion. To illustrate the new parameter space in the intermediate-redshift regime probed by LEGA-C, we explore relationships between dynamical and stellar population properties. The star-forming galaxies typically have observed stellar velocity dispersions of ~150km/s and strong H{delta} absorption (H{delta}_A_~5{AA}), while passive galaxies have higher observed stellar velocity dispersions (~200km/s) and weak H{delta} absorption (H{delta}_A_~0{AA}). Strong [OIII]5007/H{beta} ratios tend to occur mostly for galaxies with weak H{delta}_A_ or galaxies with higher observed velocity dispersion. Beyond these broad trends, we find a diversity of possible combinations of rest-frame colors, absorption-line strengths, and emission-line detections, illustrating the utility of spectroscopic measurements to more accurately understand galaxy evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/616/A118
- Title:
- Lensed QSOs light curves & spectral monitoring
- Short Name:
- J/A+A/616/A118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the framework of the Gravitational LENses and DArk MAtter (GLENDAMA) project, we present a database of nine gravitationally lensed quasars (GLQs) that have two or four images brighter than r=20mag and are located in the northern hemisphere. This new database consists of a rich variety of follow-up observations included in the GLENDAMA global archive, which is publicly available online and contains 6557 processed astronomical frames of the nine lens systems over the period 1999-2016. In addition to the GLQs, our archive also incorporates binary quasars, accretion-dominated radio-loud quasars, and other objects, where about 50% of the non-GLQs were observed as part of a campaign to identify GLQ candidates. Most observations of GLQs correspond to an ongoing long-term macro-programme with 2-10m telescopes at the Roque de los Muchachos Observatory, and these data provide information on the distribution of dark matter at all scales. We outline some previous results from the database, and we additionally obtain new results for several GLQs that update the potential of the tool for astrophysical studies.
