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1531. M31 center emission-line point-like sources
ID:
ivo://CDS.VizieR/J/MNRAS/473/4130
Title:
M31 center emission-line point-like sources
Short Name:
J/MNRAS/473/4130
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a detailed description of the wavelength, astrometric and photometric calibration plan for SITELLE, the imaging Fourier transform spectrometer attached to the Canada-France-Hawaii telescope, based on observations of a red (647-685nm) data cube of the central region (11'x11') of the Andromeda galaxy. The first application, presented in this paper, is a radial-velocity catalogue (with uncertainties of ~2-6km/s) of nearly 800 emission-line point-like sources, including ~450 new discoveries. Most of the sources are likely planetary nebulae, although we also detect five novae (having erupted in the first 8 months of 2016) and one new supernova remnant candidate.
1532. M31 Cepheid disk sample of 1st year of PS1
ID:
ivo://CDS.VizieR/J/AJ/145/106
Title:
M31 Cepheid disk sample of 1st year of PS1
Short Name:
J/AJ/145/106
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a sample of Cepheid variable stars towards M31 based on the first year of regular M31 observations of the PS1 survey in the r_P1 and i_P1 filters. We describe the selection procedure for Cepheid variable stars from the overall variable source sample and develop an automatic classification scheme using Fourier decomposition and the location of the instability strip. We find 1440 fundamental mode (classical {delta}) Cep stars, 126 Cepheids in the first overtone mode, and 147 belonging to the Population II types. 296 Cepheids could not be assigned to one of these classes and 354 Cepheids were found in other surveys. These 2009 Cepheids constitute the largest Cepheid sample in M31 known so far and the full catalog is presented in this paper. We briefly describe the properties of our sample in its spatial distribution throughout the M31 galaxy, in its age properties, and we derive an apparent period-luminosity relation (PLR) in our two bands. The Population I Cepheids nicely follow the dust pattern of the M31 disk, whereas the 147 Type II Cepheids are distributed throughout the halo of M31. We outline the time evolution of the star formation in the major ring found previously and find an age gradient. A comparison of our PLR to previous results indicates a curvature term in the PLR.
1533. MC2: redshift analysis of CIZA J2242.8+5301
ID:
ivo://CDS.VizieR/J/ApJ/805/143
Title:
MC2: redshift analysis of CIZA J2242.8+5301
Short Name:
J/ApJ/805/143
Date:
21 Oct 2021
Publisher:
CDS
Description:
X-ray and radio observations of CIZA J2242.8+5301 suggest that it is a major cluster merger. Despite being well studied in the X-ray and radio, little has been presented on the cluster structure and dynamics inferred from its galaxy population. We carried out a deep (i<25) broadband imaging survey of the system with Subaru SuprimeCam (g and i bands) and the Canada-France-Hawaii Telescope (r band), as well as a comprehensive spectroscopic survey of the cluster area (505 redshifts) using Keck DEep Imaging Multi-Object Spectrograph. We use these data to perform a comprehensive galaxy/redshift analysis of the system, which is the first step to a proper understanding of the geometry and dynamics of the merger, as well as using the merger to constrain self-interacting dark matter. We find that the system is dominated by two subclusters of comparable richness with a projected separation of 6.9'_-0.5_^+0.7^ (1.3_-0.10_^+0.13^Mpc). We find that the north and south subclusters have similar redshifts of z~0.188 with a relative line-of-sight (LOS) velocity difference of 69+/-190km/s. We also find that north and south subclusters have velocity dispersions of 1160_-90_^+100^ and 1080_-70_^+100^km/s, respectively. These correspond to masses of 16.1_-3.3_^+4.6^x10^14^ and 13.0_-2.5_^+4.0^x10^14^M_{Sun}_, respectively. While velocity dispersion measurements of merging clusters can be biased, we believe the bias in this system to be minor due to the large projected separation and nearly plane-of-sky merger configuration. We also find that the cDs of the north and south subclusters are very near their subcluster centers, in both projection (55 and 85kpc, respectively) and normalized LOS velocity (|{Delta}v|/{sigma}_v_=0.43+/-0.13 and 0.21+/-0.12 for the north and south, respectively). CIZA J2242.8+5301 is a relatively clean dissociative cluster merger with near 1:1 mass ratio, which makes it an ideal merger for studying merger-associated physical phenomena.
1534. MCT1 photometry of NGC 5128 globular clusters
ID:
ivo://CDS.VizieR/J/AJ/132/2187
Title:
MCT1 photometry of NGC 5128 globular clusters
Short Name:
J/AJ/132/2187
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the first results from an imaging program with the ACS on the Hubble Space Telescope designed to measure the structural characteristics of a wide range of globular clusters in NGC 5128, the nearest giant elliptical galaxy. From 12 ACS WFC fields we have measured a total of 62 previously known globular clusters and have discovered 69 new high-probability cluster candidates not found in any previous work. We present magnitudes and color indices for all of these, along with rough measurements of their effective diameters and ellipticities.
1535. MDFC Version 10
ID:
ivo://CDS.VizieR/II/361
Title:
MDFC Version 10
Short Name:
II/361
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Mid-infrared stellar Diameters and Fluxes compilation Catalogue (MDFC) dedicated to long-baseline interferometry at mid-infrared wavelengths (3-13um). It gathers data for half a million stars, i.e. nearly all the stars of the Hipparcos-Tycho catalogue whose spectral type is reported in the SIMBAD data base. We cross-match 26 data bases to provide basic information, binarity elements, angular diameter, magnitude and flux in the near and mid-infrared, as well as flags that allow us to identify the potential calibrators. The catalogue covers the entire sky with 465857 stars, mainly dwarfs and giants from B to M spectral types closer than 18kpc. The smallest reported values reach 0.16uJy in L and 0.1uJy in N for the flux, and 2-microarcsec for the angular diameter. We build four lists of calibrator candidates for the L and Nbands suitable with the Very Large Telescope Interferometer (VLTI) sub- and main arrays using the MATISSE instrument. We identify 1621 candidates for L and 44 candidates for N with the Auxiliary Telescopes (ATs), 375 candidates for both bands with the ATs, and 259 candidates for both bands with the Unit Telescopes (UTs). Predominantly cool giants, these sources are small and bright enough to belong to the primary lists of calibrator candidates. In the near future, we plan to measure their angular diameter with 1 per cent accuracy.
1536. M dwarfs-long-term photometric variability
ID:
ivo://CDS.VizieR/J/AJ/154/124
Title:
M dwarfs-long-term photometric variability
Short Name:
J/AJ/154/124
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report findings from a long-term photometric variability study of M dwarfs carried out at the SMARTS 0.9 m telescope at the Cerro Tololo Inter-American Observatory. As part of a multi-faceted effort to investigate the range of luminosities of M dwarfs of a given color on the Hertzsprung-Russell Diagram, 76 M dwarfs have been observed for 3-17 years in the Johnson-Kron-Cousins V band. We find that stars elevated above the center of the main sequence distribution tend to have higher levels of variability, likely caused by magnetic activity, than their fainter counterparts below the center. This study provides insight into how the long-term magnetic activity of these stars may be affecting their sizes, luminosities, and thus positions on the H-R Diagram.
1537. Mean Spectra for upper AGB stars
ID:
ivo://CDS.VizieR/J/A+A/393/167
Title:
Mean Spectra for upper AGB stars
Short Name:
J/A+A/393/167
Date:
21 Oct 2021
Publisher:
CDS
Description:
Provided are average spectra extending from 510 to 2490nm for: - Oxygen rich, optically visible LPVs (temperature sequence based on the colour I-K); - Carbon rich, optically visible LPVs (temperature sequence based on the colour R-H, and C/O sequence); - Oxygen rich, dust-enshrouded LPVs (reddened versions of the coolest optically visible average); - Carbon rich, dust-enshrouded LPVs (reddened versions of the coolest optically visible average).
1538. Measuring dark energy properties with PS1 SNe. II.
ID:
ivo://CDS.VizieR/J/ApJ/857/51
Title:
Measuring dark energy properties with PS1 SNe. II.
Short Name:
J/ApJ/857/51
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z<0.1) SNe Ia to measure cosmological parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased cosmological parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with cosmic microwave background (CMB) constraints from Planck, we measure the dark energy equation-of-state parameter w to be -0.989+/-0.057 (stat+sys). If w evolves with redshift as w(a)=w0+wa(1-a), we find w0=-0.912+/-0.149 and wa=-0.513+/-0.826. These results are consistent with cosmological parameters from the Joint Light-curve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a w differing by more than 2% from the baseline measurement. The systematic uncertainty on w due to marginalizing over CC SN contamination, {sigma}_w_^CC^=0.012, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6{sigma}) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-z analyses. Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
1539. Medium-band photometry RM of 5 nearby AGNs
ID:
ivo://CDS.VizieR/J/ApJ/884/103
Title:
Medium-band photometry RM of 5 nearby AGNs
Short Name:
J/ApJ/884/103
Date:
21 Oct 2021
Publisher:
CDS
Description:
Reverberation mapping (RM) is one of the most efficient ways to investigate the broad-line region around the central supermassive black holes of active galactic nuclei (AGNs). A common way of performing the RM is to perform a long term spectroscopic monitoring of AGNs, but the spectroscopic monitoring campaign of a large number of AGNs requires an extensive amount of observing time of medium to large size telescopes. As an alternative way, we present the results of photometric RM with medium-band photometry. As the widths of medium-band filters match well with the widths of AGN broad emission lines, the medium-band observation with small telescopes can be a cost-effective way to perform RM. We monitored five nearby AGNs with available spectroscopic RM results showing days to weeks scale variability. Observations were performed for ~3 months with an average of 3 days cadence using three medium-band filters on a 0.43m telescope. The time lags between the continuum and the H{alpha} emission line light curves are calculated using the JAVELIN software and the discrete correlation function. We find time lags of 1.5-15.9d for these AGNs, which are consistent with the time lags derived from previous spectroscopic RM measurements. This result demonstrates that even a 0.5m class telescope can perform RM with medium-bands. Furthermore, we show that RM for tens of thousands AGNs is possible with a dedicated 1m class telescope.
1540. MegaCam survey of outer halo satellites. I.
ID:
ivo://CDS.VizieR/J/ApJ/860/65
Title:
MegaCam survey of outer halo satellites. I.
Short Name:
J/ApJ/860/65
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe a deep, systematic imaging study of satellites in the outer halo of the Milky Way. Our sample consists of 58 stellar overdensities --i.e., substructures classified as either globular clusters, classical dwarf galaxies, or ultra-faint dwarf galaxies-that are located at Galactocentric distances of R_GC_>=25kpc (outer halo) and out to ~400kpc. This includes 44 objects for which we have acquired deep, wide-field, g- and r-band imaging with the MegaCam mosaic cameras on the 3.6m Canada-France-Hawaii Telescope and the 6.5m Magellan-Clay telescope. These data are supplemented by archival imaging, or published gr photometry, for an additional 14 objects, most of which were discovered recently in the Dark Energy Survey (DES). We describe the scientific motivation for our survey, including sample selection, observing strategy, data reduction pipeline, calibration procedures, and the depth and precision of the photometry. The typical 5{sigma} point-source limiting magnitudes for our MegaCam imaging-which collectively covers an area of ~52deg^2^ --are g_lim_~25.6 and r_lim_~25.3 AB mag. These limits are comparable to those from the coadded DES images and are roughly a half-magnitude deeper than will be reached in a single visit with the Large Synoptic Survey Telescope. Our photometric catalog thus provides the deepest and most uniform photometric database of Milky Way satellites available for the foreseeable future. In other papers in this series, we have used these data to explore the blue straggler populations in these objects, their density distributions, star formation histories, scaling relations, and possible foreground structures.