- ID:
- ivo://CDS.VizieR/J/A+A/641/A129
- Title:
- Multi-band photometry catalogue of 185 DSFGs
- Short Name:
- J/A+A/641/A129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dusty high-z galaxies are extreme objects with high star formation rates (SFRs) and luminosities. Characterising the properties of this population and analysing their evolution over cosmic time is key to understanding galaxy evolution in the early Universe. We select a sample of high-z dusty star-forming galaxies (DSFGs) and evaluate their position on the main sequence (MS) of star-forming galaxies, the well-known correlation between stellar mass and SFR. We aim to understand the causes of their high star formation and quantify the percentage of DSFGs that lie above the MS. We adopted a multi-wavelength approach with data from optical to submillimetre wavelengths from surveys at the North Ecliptic Pole (NEP) to study a submillimetre sample of high-redshift galaxies. Two submillimetre selection methods were used, including: sources selected at 850um with the Sub-millimetre Common-User Bolometer Array 2) SCUBA-2 instrument and Herschel-Spectral and Photometric Imaging Receiver (SPIRE) selected sources (colour-colour diagrams and 500um risers), finding that 185 have good multi-wavelength coverage. The resulting sample of 185 high-z candidates was further studied by spectral energy distribution (SED) fitting with the CIGALE fitting code. We derived photometric redshifts, stellar masses, SFRs, and additional physical parameters, such as the infrared luminosity and active galactic nuclei (AGN) contribution. We find that the Herschel-SPIRE selected DSFGs generally have higher redshifts (z=2.57^+0.08^_-0.09_) than sources that are selected solely by the SCUBA-2 method (z=1.45^+0.21^_-0.06_). We find moderate SFRs (797^+108^_-50_M_{sun}/yr}), which are typically lower than those found in other studies. We find that the different results in the literature are, only in part, due to selection effects, as even in the most extreme cases, SFRs are still lower than a few thousand solar masses per year. The difference in measured SFRs affects the position of DSFGs on the MS of galaxies; most of the DSFGs lie on the MS (60%). Finally, we find that the star formation efficiency (SFE) depends on the epoch and intensity of the star formation burst in the galaxy; the later the burst, the more intense the star formation. We discuss whether the higher SFEs in DSFGs could be due to mergers.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/743/154
- Title:
- Multi-band photometry of GRB 110205A + 110213A
- Short Name:
- J/ApJ/743/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present rich, early-time, multiband data sets for two Swift events, GRB 110205A and GRB 110213A. The former shows optical emission since the early stages of the prompt phase, followed by the steep rising in flux up to ~1000s after the burst (t^-{alpha}^ with {alpha}=-6.13+/-0.75). We discuss this feature in the context of the reverse-shock scenario and interpret the following single power-law decay as being forward-shock dominated. Polarization measurements, obtained with the RINGO2 instrument mounted on the Liverpool Telescope, also provide hints on the nature of the emitting ejecta. The latter event, instead, displays a very peculiar optical to near-infrared light curve, with two achromatic peaks. In this case, while the first peak is probably due to the onset of the afterglow, we interpret the second peak to be produced by newly injected material, signifying a late-time activity of the central engine.
- ID:
- ivo://CDS.VizieR/J/ApJ/897/180
- Title:
- Multiband photometry of microlensing event Kojima-1
- Short Name:
- J/ApJ/897/180
- Date:
- 16 Mar 2022 00:48:14
- Publisher:
- CDS
- Description:
- We report the lens mass and distance measurements of the nearby microlensing event TCPJ05074264+2447555 (Kojima-1). We measure the microlens parallax vector {pi}_E_ using Spitzer and ground-based light curves with constraints on the direction of lens-source relative proper motion derived from Very Large Telescope Interferometer (VLTI) GRAVITY observations. Combining this {pi}_E_ determination with the angular Einstein radius {theta}_E_ measured by VLTI-GRAVITY observations, we find that the lens is a star with mass M_L_=0.495{+/-}0.063M{odot} at a distance DL=429{+/-}21pc. We find that the blended light basically all comes from the lens. The lens-source proper motion is {mu}_rel,hel_=26.55{+/-}0.36mas/yr, so with currently available adaptive-optics instruments, the lens and source can be resolved in 2021. This is the first microlensing event whose lens mass is unambiguously measured by interferometry+satellite-parallax observations, which opens a new window for mass measurements of isolated objects such as stellar-mass black holes.
- ID:
- ivo://CDS.VizieR/J/PASP/122/144
- Title:
- Multiband photometry of V725 Sgr
- Short Name:
- J/PASP/122/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- V725 Sgr is a rather peculiar variable that showed a period increase during part of the twentieth century. Its behavior is attributed to rapid stellar evolution. V725 Sgr was monitored in V, R, I and J, H, K with the REM telescope, on La Silla, from 2008 August to 2009 November. Its light variation does not show a well-defined cyclic behavior. Its current V is similar to what it was 30-40yrs ago. Its published motion suggests that V725 Sgr is located at a few kiloparsecs from the Sun. This implies that V725 Sgr is a giant rather than a supergiant star. From its mean colors we conclude that V725 Sgr is now an irregular variable of spectral type ~K4 III.
- ID:
- ivo://CDS.VizieR/J/A+A/556/A10
- Title:
- Multiband surface photometry of 21 BCGs
- Short Name:
- J/A+A/556/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep surface photometry of a volume-limited sample of 21 UM emission line galaxies in broadband optical UBVRI and near infra-red (NIR) HKs filters. The sample comprises 19 blue compact galaxies (BCGs) and two spirals. For some targets the exposure times are the deepest to date. For the BCG UM462 we observe a previously undetected second disk component beyond a surface brightness level of mu_B_=26mag/arcsec^2^. This is a true low surface brightness component with central surface brightness mu_0_=24.1mag/arcsec^2^ and scale length h_r_=1.5kpc. All BCGs are dwarfs, with M_B_>=-18, and very compact, with an average scale length of h_r_~1kpc. We separate the burst and host populations for each galaxy and compare them to stellar evolutionary models with and without nebular emission contribution. We also measure the A_180_ asymmetry in all filters and detect a shift from optical to NIR in the average asymmetry of the sample. This shift seems to be correlated with the morphological class of the BCGs. Using the color-asymmetry relation, we identify five BCGs in the sample as mergers, which is confirmed by their morphological class. Though clearly separated from normal galaxies in the concentration-asymmetry parameter space, we find that it is not possible to distinguish luminous starbursting BCGs from the merely star forming low luminosity BCGs.
- ID:
- ivo://CDS.VizieR/J/ApJ/728/48
- Title:
- Multicolor eclipse data for 6 new binaries
- Short Name:
- J/ApJ/728/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery and characterization of six new M dwarf eclipsing binary systems. The 12 stars in these eclipsing systems have masses spanning 0.38-0.59M_{sun}_ and orbital periods of 0.6-1.7 days, with typical uncertainties of ~0.3% in mass and ~0.5%-2.0% in radius. Combined with six known systems with high-precision measurements, our results reveal an intriguing trend in the low-mass regime. For stars with M=0.35-0.80M_{sun}_, components in short-period binary systems (P<~1 day; 12 stars) have radii which are inflated by up to 10% ({mu}=4.8+/-1.0%) with respect to evolutionary models for low-mass main-sequence stars, whereas components in longer-period systems (>1.5 days; 12 stars) tend to have smaller radii ({mu}=1.7+/-0.7%).
- ID:
- ivo://CDS.VizieR/J/ApJS/149/53
- Title:
- Multicolor photometry of A2255 galaxies
- Short Name:
- J/ApJS/149/53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present our optical multicolor photometry for the nearby cluster of galaxies A2255 with 13 intermediate filters in the Beijing-Arizona-Taiwan-Connecticut (BATC) system (see Cat. II/262), which cover an optical wavelength range from 3000 to 10000{AA}. The spectral energy distributions (SEDs) in the optical band for more than 7000 sources are achieved down to V~20 in a field of 58'x58' entered on this rich cluster. A2255 has been observed by the Sloan Digital Sky Survey (SDSS) down to V~17.5 spectroscopically and r'~22.0 photometrically. A method of combining the SDSS photometric data in five broad bands and the BATC SEDs is then explored. A sample of 254 galaxies with known redshifts in the region of A2255 is constructed for testing the reliability of the method of combining SEDs. Our application of the technique of photometric redshift on this sample shows that the combined SEDs with higher resolution could lead to a more accurate estimate of photometric redshift. Based on 214 spectroscopically confirmed member galaxies, spatial and dynamical properties of this cluster are studied.
- ID:
- ivo://CDS.VizieR/J/PAZh/25/764
- Title:
- Multicolor photometry of RY Sct
- Short Name:
- J/PAZh/25/764
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New uvby-{beta} photometry of the unique binary RY Sct is reported. The results were interpreted using the light-curve synthesis method.
- ID:
- ivo://CDS.VizieR/J/AJ/144/191
- Title:
- Multicolor photometry of 135 star clusters in M31
- Short Name:
- J/AJ/144/191
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present photometry for young star clusters in M31, which are selected from Caldwell et al. These star clusters have been observed as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey from 1995 February to 2008 March. The BATC images including these star clusters are taken with 15 intermediate-band filters covering 3000-10000{AA}. Combined with photometry in the GALEX far- and near-ultraviolet, broadband UBV RI, SDSS ugriz, and infrared JHK_s_ of Two Micron All Sky Survey, we obtain their accurate spectral energy distributions (SEDs) from 1538 to 20000{AA}. We derive these star clusters' ages and masses by comparing their SEDs with stellar population synthesis models. Our results are in good agreement with previous determinations. The mean value of age and mass of young clusters (<2Gyr) is about 385Myr and 2x10^4^M_{sun}_, respectively. There are two distinct peaks in the age distribution, a highest peak at age ~60Myr and a secondary peak around 250Myr, while the mass distribution shows a single peak around 10^4^M_{sun}_. A few young star clusters have two-body relaxation times greater than their ages, indicating that those clusters have not been well dynamically relaxed and therefore have not established the thermal equilibrium. There are several regions showing aggregations of young star clusters around the 10kpc ring and the outer ring, indicating that the distribution of the young star clusters is well correlated with M31's star-forming regions. The young massive star clusters (age<=100Myr and mass>=10^4^M_{sun}_) show apparent concentration around the ring splitting region, suggesting a recent passage of a satellite galaxy (M32) through M31 disk.
- ID:
- ivo://CDS.VizieR/J/A+A/556/A55
- Title:
- Multi-color photometry of star-forming galaxies
- Short Name:
- J/A+A/556/A55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We estimate the galaxy stellar mass function and stellar mass density for star-forming and quiescent galaxies with 0.2<z<4. We construct a large, deep sample of galaxies selected using the new UltraVISTA DR1 data release (Cat. J/A+A/544/A156). Our analysis is based on precise 30-band photometric redshifts. By comparing these photometric redshifts with 10800 spectroscopic redshifts from the zCOSMOS bright (Cat. J/ApJS/172/70) and faint (Lilly et al. in prep) surveys, we find an accuracy of sigma(dz/(1+z))=0.008 at i<22.5 and sigma(dz/(1+z))=0.03 at 1.5<z<4.
