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3991. MIPS observations of h and {chi} Persei
ID:
ivo://CDS.VizieR/J/ApJ/672/558
Title:
MIPS observations of h and {chi} Persei
Short Name:
J/ApJ/672/558
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe Spitzer MIPS observations of the double cluster, h and {chi} Persei, covering a ~0.6deg^2^ area surrounding the cores of both clusters. The data are combined with IRAC and 2MASS data to investigate ~616 sources from 1.25-24um. We use the long-baseline Ks-[24] color to identify two populations with IR excess indicative of circumstellar material: Be stars with 24um excess from optically thin free-free emission, and 17 fainter sources (J~14-15) with [24] excess consistent with a circumstellar disk. The frequency of IR excess for the fainter sources increases from 4.5 to 24um. The IR excess is likely due to debris from the planet formation process. The wavelength-dependent behavior is consistent with an inside-out clearing of circumstellar disks. A comparison of the 24um excess population in h and {chi} Per sources with results for other clusters shows that 24um emission from debris disks "rises" from 5 to 10Myr, peaks at ~10-15Myr, and then "falls" from ~15-20Myr to 1Gyr.
3992. MIPS photometry for Herschel SAG2 Programs
ID:
ivo://CDS.VizieR/J/MNRAS/423/197
Title:
MIPS photometry for Herschel SAG2 Programs
Short Name:
J/MNRAS/423/197
Date:
21 Oct 2021
Publisher:
CDS
Description:
We provide an overview of ancillary 24, 70, and 160 micron data from the Multiband Imaging Photometer for Spitzer (MIPS) that are intended to complement the 70-500 micron Herschel Space Observatory photometry data for nearby galaxies obtained by the Herschel-SPIRE Local Galaxies Guaranteed Time Programs and the Herschel Virgo Cluster Survey. The MIPS data can be used to extend the photometry to wave bands that are not observed in these Herschel surveys and to check the photometry in cases where Herschel performs observations at the same wavelengths. Additionally, we measured globally-integrated 24-160 micron flux densities for the galaxies in the sample that can be used for the construction of spectral energy distributions. Using MIPS photometry published by other references, we have confirmed that we are obtaining accurate photometry for these galaxies.
3993. MIPS sources near the South Ecliptic Pole
ID:
ivo://CDS.VizieR/J/ApJS/191/212
Title:
MIPS sources near the South Ecliptic Pole
Short Name:
J/ApJS/191/212
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have imaged an 11.5deg^2^ region of sky toward the South Ecliptic Pole (SEP; J0443-5340) at 24 and 70um with MIPS, the Multiband Imaging Photometer for Spitzer. This region is coincident with a field mapped at longer wavelengths by AKARI and BLAST. We discuss our data reduction and source extraction procedures. The median 1{sigma} depths of the maps are 47uJy/beam at 24um and 4.3mJy/beam at 70um. At 24um, we identify 93098 point sources with signal-to-noise ratio (S/N)>=5 and an additional 63 resolved galaxies; at 70um we identify 891 point sources with S/N>=6. From simulations, we determine a false detection rate of 1.8% (1.1%) for the 24um (70um) catalog. The 24 and 70um point-source catalogs are 80% complete at 230uJy and 11mJy, respectively.
3994. MIPS 24um calibrators
ID:
ivo://CDS.VizieR/J/PASP/119/994
Title:
MIPS 24um calibrators
Short Name:
J/PASP/119/994
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the stellar calibrator sample and the conversion from instrumental to physical units for the 24{mu}m channel of the Multiband Imaging Photometer for Spitzer (MIPS). The primary calibrators are A stars, and the calibration factor based on those stars is 4.54x10^-2^MJy/sr/(DN/s), with a nominal uncertainty of 2%. We discuss the data reduction procedures required to attain this accuracy; without these procedures, the calibration factor obtained using the automated pipeline at the Spitzer Science Center is 1.6%+/-0.6% lower. We extend this work to predict 24{mu}m flux densities for a sample of 238 stars that covers a larger range of flux densities and spectral types. We present a total of 348 measurements of 141 stars at 24{mu}m. This sample covers a factor of ~460 in 24{mu}m flux density, from 8.6mJy up to 4.0Jy. We show that the calibration is linear over that range with respect to target flux and background level. The calibration is based on observations made using 3s exposures; a preliminary analysis shows that the calibration factor may be 1% and 2% lower for 10 and 30s exposures, respectively. We also demonstrate that the calibration is very stable: over the course of the mission, repeated measurements of our routine calibrator, HD 159330, show a rms scatter of only 0.4%. Finally, we show that the point-spread function (PSF) is well measured and allows us to calibrate extended sources accurately; Infrared Astronomy Satellite (IRAS) and MIPS measurements of a sample of nearby galaxies are identical within the uncertainties.
3995. MIPS 24um nebulae
ID:
ivo://CDS.VizieR/J/MNRAS/405/1047
Title:
MIPS 24um nebulae
Short Name:
J/MNRAS/405/1047
Date:
21 Oct 2021
Publisher:
CDS
Description:
Massive evolved stars lose a large fraction of their mass via copious stellar wind or instant outbursts. During certain evolutionary phases, they can be identified by the presence of their circumstellar nebulae. In this paper, we present the results of a search for compact nebulae (reminiscent of circumstellar nebulae around evolved massive stars) using archival 24um data obtained with the Multiband Imaging Photometer for Spitzer. We have discovered 115 nebulae, most of which bear a striking resemblance to the circumstellar nebulae associated with luminous blue variables (LBVs) and late WN-type (WNL) Wolf-Rayet (WR) stars in the Milky Way and the Large Magellanic Cloud (LMC).
3996. MIPS 24um observations of the HDFS
ID:
ivo://CDS.VizieR/J/ApJ/723/1110
Title:
MIPS 24um observations of the HDFS
Short Name:
J/ApJ/723/1110
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present MIPS 24um observations of the Hubble Deep Field South taken with the Spitzer Space Telescope. The resulting image is 254arcmin^2^ in size and has a sensitivity ranging between ~12 and ~30uJy rms, with a median sensitivity of ~20uJy rms. A total of 495 sources have been catalogued with a signal-to-noise ratio greater than 5{sigma}. The source catalog is presented as well as source counts which have been corrected for completeness and flux boosting. The IR sources are then combined with MUSYC optical/NIR and ATHDFS radio observations to obtain redshifts and radio flux densities of the sample. We use the IR/radio flux density ratio (q_24_) to explore the IR-radio correlation for this IR sample and find q_24_=0.71+/-0.31 for sources detected in both IR and radio. The results are extended by stacking IR sources not detected in the radio observations and we derive an average q_24_ for redshift bins between 0<z<2.5. We find that the high-redshift (z>1) sources have an average q_24_ ratio which is better fit by local LIRG SEDs rather than local ULIRG SEDs, indicating that high-redshift ULIRGs differ in their IR/radio properties. So, ULIRGs at high-redshift have SEDs different from those found locally. Infrared-faint radio sources are examined, and while nine radio sources do not have an MIPS detection and are therefore radio-loud active galactic nuclei (AGNs), only one radio source has an extreme IRAC 3.6um to radio flux density ratio indicating it is a radio-loud AGN at z>1.
3997. M31 IRAC 3.6/4.5um extended survey
ID:
ivo://CDS.VizieR/J/MNRAS/459/1403
Title:
M31 IRAC 3.6/4.5um extended survey
Short Name:
J/MNRAS/459/1403
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results from an extended survey of the Andromeda galaxy (M31) using 41.1h of observations by Spitzer-IRAC at 3.6 and 4.5{mu}m. This survey extends previous observations to the outer disc and halo, covering total lengths of 44 and 66 along the minor and major axes, respectively. We have produced surface brightness profiles by combining the integrated light from background-corrected maps with stellar counts from a new catalogue of point sources. Using auxiliary catalogues, we have carried out a statistical analysis in colour-magnitude space to discriminate M31 objects from foreground Milky Way stars and background galaxies. The catalogue includes 426 529 sources, of which 66 per cent have been assigned probability values to identify M31 objects with magnitude depths of [3.6]=19.0+/-0.2, [4.5]=18.7+/-0.2. We discuss applications of our data for constraining the stellar mass and characterizing point sources in the outer radii.
3998. Mira-like variables from the KELT survey
ID:
ivo://CDS.VizieR/J/ApJS/247/44
Title:
Mira-like variables from the KELT survey
Short Name:
J/ApJS/247/44
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a sample of 4132 Mira-like variables (red variables with long periods and high amplitudes) in the Kilodegree Extremely Little Telescope (KELT) survey. Of these, 376 are new Mira-like detections. We used Two Micron All Sky Survey (2MASS) colors to identify candidate asymptotic giant branch stars. We searched for photometric variability among the candidate asymptotic giant branch stars and identified stars that show periodic variability. We selected variables with high amplitudes and strong periodic behavior using a Random Forest classifier. Of the sample of 4132 Mira-like variables, we estimate that 70% are Miras and 30% are semiregular (SR) variables. We also adopt the method of using (W_RP_-W_Ks_) versus (J-Ks) colors in distinguishing between O-rich and C-rich Miras and find it to be an improvement over 2MASS colors.
3999. Mira stars discovered in LAMOST DR4
ID:
ivo://CDS.VizieR/J/ApJS/232/16
Title:
Mira stars discovered in LAMOST DR4
Short Name:
J/ApJS/232/16
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on an extensive spectral study of a photometrically confirmed sample of Mira variables, we find a relationship between the relative Balmer emission-line strengths and spectral temperatures of O-rich Mira stars. The F_H{delta}_/F_H{gamma}_ flux ratio increases from less than unity to five as stars cool down from M0 to M10, which is likely driven by increasing TiO absorption above the deepest shock-emitting regions. We also discuss the relationship between the equivalent widths of the Balmer emission lines and the photometric luminosity phase of our Mira sample stars. Using our 291 Mira spectra as templates for reference, 191 Mira candidates are newly identified from the LAMOST DR4 catalog. We summarize the criteria adopted to select Mira candidates based on emission-line indices and molecular absorption bands. This enlarged spectral sample of Mira variables has the potential to contribute significantly to our knowledge of the optical properties of Mira stars and will facilitate further studies of these late-type, long-period variables.
4000. Mira Variables in the OGLE Bulge fields
ID:
ivo://CDS.VizieR/J/A+A/443/143
Title:
Mira Variables in the OGLE Bulge fields
Short Name:
J/A+A/443/143
Date:
21 Oct 2021
Publisher:
CDS
Description:
The 222000 I-band light curves of variable stars detected by the OGLE-II survey in the direction of the Galactic Bulge have been fitted and also correlated with the DENIS and 2MASS all-sky release databases and with lists of known objects. Light-curves and the results of the light-curve fitting (periods and amplitudes) and DENIS and 2MASS data are presented for 2691 objects with I-band semi-amplitude larger than 0.45 magnitude, corresponding to classical Mira variables.