- ID:
- ivo://CDS.VizieR/J/ApJ/897/89
- Title:
- 1482 Gaussian clumps in the Central Molecular Zone
- Short Name:
- J/ApJ/897/89
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We carry out a systematic study of the density structure of gas in the Central Molecular Zone (CMZ) in the Galactic center by extracting clumps from the APEX Telescope Large Area Survey of the Galaxy survey at 870{mu}m. We find that the clumps follow a scaling of m={rho}_0_r^3^, which corresponds to a characteristic density of n_H_2__=1.6x10^3^/cm^3^ ({rho}_0_=112M{sun}/pc^3^) with a variation of ~0.5dex, where we assumed a gas-to-dust mass ratio of 100. This characteristic density can be interpreted as the result of thermal pressure equilibrium between the molecular gas and the warm ambient interstellar medium. Such an equilibrium can plausibly be established since shear has approximately the same strength as self-gravity. Our findings may explain the fact that star formation in the CMZ is highly inefficient compared to the rest of the Milky Way disk. We also identify a population of clumps whose densities are two orders of magnitudes higher in the vicinity of the Sgr B2 region, which we propose are produced by collisions between the clumps of lower densities. For these collisions to occur, processes such as compressive tides probably have created the appropriate condition by assembling the clumps together.
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- ID:
- ivo://CDS.VizieR/J/AJ/127/2455
- Title:
- Gemini Deep Deep Survey (GDDS)
- Short Name:
- J/AJ/127/2455
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Gemini Deep Deep Survey (GDDS) is an ultradeep (K<20.6mag, I<24.5mag) redshift survey targeting galaxies in the "redshift desert" between z=1 and z=2. The primary goal of the survey is to constrain the space density at high redshift of evolved high-mass galaxies. We obtained 309 spectra in four widely separated 30-arcmin^2^ fields using the Gemini North telescope and the Gemini Multi-Object Spectrograph (GMOS). The spectra define a one-in-two sparse sample of the reddest and most luminous galaxies near the I-K versus I color-magnitude track mapped out by passively evolving galaxies in the redshift interval 0.8<z<1.8. This sample is augmented by a one-in-seven sparse sample of the remaining high-redshift galaxy population. The GMOS spectrograph was operating in a nod-and-shuffle mode, which enabled us to remove sky contamination with high precision, even for typical exposures times of 20-30hr per field. The resulting spectra are the deepest ever obtained. In this paper we present our sample of 309 spectra, along with redshifts, identifications of spectral features, and photometry. This makes the GDDS the largest and most complete infrared-selected survey probing the redshift desert. The seven-band (VRIz'JHK_s_) photometry is taken from the Las Campanas Infrared Survey (Cat. <VII/228>).
- ID:
- ivo://CDS.VizieR/J/ApJ/846/160
- Title:
- 6.7GHz Class II methanol maser survey
- Short Name:
- J/ApJ/846/160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a systematic 6.7GHz Class II methanol maser survey using the Shanghai Tianma Radio Telescope toward targets selected from the all-sky Wide-Field Infrared Survey Explorer (WISE) point catalog. In this paper, we report the results from the survey of those at high Galactic latitudes, i.e., |b|>2{deg}. Of 1473 selected WISE point sources at high latitude, 17 point positions that were actually associated with 12 sources were detected with maser emission, reflecting the rarity (1%-2%) of methanol masers in the region away from the Galactic plane. Out of the 12 sources, 3 are detected for the first time. The spectral energy distribution at infrared bands shows that these new detected masers occur in the massive star-forming regions. Compared to previous detections, the methanol maser changes significantly in both spectral profiles and flux densities. The infrared WISE images show that almost all of these masers are located in the positions of the bright WISE point sources. Compared to the methanol masers at the Galactic plane, these high-latitude methanol masers provide good tracers for investigating the physics and kinematics around massive young stellar objects, because they are believed to be less affected by the surrounding cluster environment.
- ID:
- ivo://CDS.VizieR/J/ApJS/200/5
- Title:
- 95GHz class I methanol maser survey
- Short Name:
- J/ApJS/200/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a survey with the Purple Mountain Observatory 13.7m radio telescope for class I methanol masers from the 95GHz (8_0_-7_1_A^+^) transition. Two hundred and fourteen target sources were selected by combining information from both the Spitzer GLIMPSE and 1.1mm Bolocam Galactic Plane Survey (BGPS) catalogs. The observed sources satisfy the GLIMPSE mid-IR criteria of [3.6]-[4.5]>1.3, [3.6]-[5.8]>2.5, [3.6]-[8.0]>2.5 and 8.0um mag less than 10; they also have an associated 1.1mm BGPS source. Class I methanol maser emission was detected in 63 sources, corresponding to a detection rate of 29% for this survey. For the majority of detections (43), this is the first identification of class I methanol masers associated with these sources. We show that the intensity of the class I methanol maser emission is not closely related to mid-IR intensity or the colors of the GLIMPSE point sources; however, it is closely correlated with properties (mass and beam-averaged column density) of the BGPS sources. Comparison of measures of star formation activity for the BGPS sources with and without class I methanol masers indicates that the sources with class I methanol masers usually have higher column density and larger flux density than those without them.
- ID:
- ivo://CDS.VizieR/J/ApJ/769/20
- Title:
- 22GHz H_2_O maser survey toward IR sources
- Short Name:
- J/ApJ/769/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a 22GHz H_2_O maser survey toward a new sample of asymptotic giant branch (AGB) and post-AGB star candidates. Most of the objects are selected for the first time based on the AKARI data, which have high flux sensitivity in the mid-infrared ranges. We aim at finding H_2_O maser sources in the transient phase between the AGB and post-AGB stages of evolution, where the envelopes start to develop large deviations from spherical symmetry. The observations were carried out with the Effelsberg 100m radio telescope. Among 204 observed objects, 63 detections (36 new) were obtained. We found four objects that may be "water fountain" sources (IRAS 15193+3132, IRAS 18056-1514, OH 16.3-3.0, and IRAS 18455+0448). They possess an H_2_O maser velocity coverage much smaller than those in other known water fountains. However, the coverage is still larger than that of the 1612MHz OH maser. It implies that there is an outflow with a higher velocity than the envelope expansion velocity (typically <=25km/s), meeting the criterion of the water fountain class. We suggest that these candidates are possibly oxygen-rich late AGB or early post-AGB stars in a stage of evolution immediately after the spherically symmetric AGB mass loss has ceased.
- ID:
- ivo://CDS.VizieR/J/A+A/418/103
- Title:
- 86GHz SiO maser survey in the Inner Galaxy
- Short Name:
- J/A+A/418/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a compilation and study of DENIS, 2MASS, ISOGAL, MSX and IRAS 1-25 microns photometry for a sample of 441 late-type stars in the inner Galaxy, which we previously searched for 86GHz SiO maser emission (Messineo et al., 2002, Cat. <J/A+A/393/115>). The comparison of the DENIS and 2MASS J and Ks magnitudes shows that most of the SiO targets are indeed variable stars. The MSX colours and the IRAS [12]-[25] colour of our SiO targets are consistent with those of Mira type stars with dust silicate feature at 9.7 microns feature in emission, indicating only a moderate mass-loss rate.
667. GLADE catalog
- ID:
- ivo://CDS.VizieR/VII/275
- Title:
- GLADE catalog
- Short Name:
- VII/275
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We are introducing a value-added full-sky galaxy catalog with high completeness for identifying gravitational wave (GW) sources in order to support future electromagnetic (EM) follow-up projects of the LIGO/Virgo Collaboration. The catalog GLADE (Galaxy List for the Advanced Detector Era) has been constructed (combined and matched) from four existing galaxy catalogs: GWGC, 2MPZ, 2MASS XSC and HyperLEDA. It contains 1918147 galaxies, which is two orders of magnitude greater than the number of galaxies in the GWGC catalog alone (53312), which is currently in use by the collaboration. Furthermore we considered it as a crucial requirement towards the catalog to contain B-band magnitudes and distances for all entries. Therefore we have associated these properties for 548876 2MASS galaxies which lacked them with a regression algorithm teached on a subsample of the 2MPZ catalog. Our catalog is complete to 73Mpc and even at 300Mpc has a relatively high completeness (53%). Naturally, our catalog could be used in a broad range of various astrophysical projects besides EM follow-up efforts.We are introducing a value-added full-sky galaxy catalog with high completeness for identifying gravitational wave (GW) sources in order to support future electromagnetic (EM) follow-up projects of the LIGO/Virgo Collaboration. The catalog has been constructed (combined and matched) from four existing galaxy catalogs: GWGC, 2MPZ, 2MASS XSC and HyperLEDA. It contains 1918147 galaxies, which is two orders of magnitude greater than the number of galaxies in the GWGC catalog alone (53312), which is currently in use by the collaboration. Furthermore we considered it as a crucial requirement towards the catalog to contain B-band magnitudes and distances for all entries. Therefore we have associated these properties for 548,876 2MASS galaxies which lacked them with a regression algorithm teached on a subsample of the 2MPZ catalog. Our catalog is complete to 73 Mpc and even at 300 Mpc has a relatively high completeness (53%). Naturally, our catalog could be used in a broad range of various astrophysical projects besides EM follow-up efforts. For a brief overview of the GLADE project, check out the talk slides (http://aquarius.elte.hu/glade/GLADE_GDalya_LVC2015September.pdf) presented at the 2015 September LIGO-Virgo Collaboration Meeting in Budapest, Hungary. If you have any questions or suggestions about the catalog, please send us an email: dalyag@caesar.elte.hu
668. GLADE v2.3 catalog
- ID:
- ivo://CDS.VizieR/VII/281
- Title:
- GLADE v2.3 catalog
- Short Name:
- VII/281
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We introduce a value-added full-sky catalogue of galaxies, named as Galaxy List for the Advanced Detector Era, or GLADE. The purpose of this catalogue is to (i) help identifications of host candidates for gravitational-wave events, (ii) support target selections for electromagnetic follow-up observations of gravitational-wave candidates, (iii) provide input data on the matter distribution of the local Universe for astrophysical or cosmological simulations, and (iv) help identifications of host candidates for poorly localized electromagnetic transients, such as gamma-ray bursts observed with the InterPlanetary Network. Both being potential hosts of astrophysical sources of gravitational waves, GLADE includes inactive and active galaxies as well. GLADE was constructed by cross-matching and combining data from five separate (but not independent) astronomical catalogues: GWGC, 2MPZ, 2MASS XSC, HyperLEDA, and SDSS-DR12Q. GLADE is complete up to d_L_=37^+3^_-4_Mpc in terms of the cumulative B-band luminosity of galaxies within luminosity distance dL, and contains all of the brightest galaxies giving half of the total B-band luminosity up to d_L_=91Mpc. As B-band luminosity is expected to be a tracer of binary neutron star mergers (currently the prime targets of joint GW+EM detections), our completeness measures can be used as estimations of completeness for containing all binary neutron star merger hosts in the local Universe.
- ID:
- ivo://CDS.VizieR/J/PASP/122/885
- Title:
- Gliese catalog star/2MASS cross identifications
- Short Name:
- J/PASP/122/885
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide precise J2000/epoch 2000 coordinates and cross-identifications to sources in the 2MASS Point Source Catalog for nearly all stars in the Gliese, Gliese-Jahreiss, and Woolley catalogs of nearby stars. The only Gliese objects where we were not successful are two Gliese sources that are actually QSOs; two proposed companions to brighter stars, which we believe do not exist; four stars included in one of the catalogs but identified there as only optical companions; one probable plate flaw; and two stars that simply remain unrecovered. For the 4251 recovered stars, 2693 have coordinates based on Hipparcos positions, 1549 have coordinates based on 2MASS data, and 9 have positions from other astrometric sources. All positions have been calculated at epoch 2000 using proper motions from the literature, which are also given here.
- ID:
- ivo://CDS.VizieR/II/293
- Title:
- GLIMPSE Source Catalog (I + II + 3D)
- Short Name:
- II/293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Galactic Legacy Infrared Midplane Survey Extraordinaire (GLIMPSE), is a survey of Galactic Plane central parts made with the Infrared Array Camera (IRAC) aboard the Spitzer Space Telescope (SST). It covers approximately 220 square degrees, between galactic longitudes +/-65{deg} and +/-1{deg} in galactic latitude (up to 4.2{deg} in the central parts). The four IRAC bands are centered at approximately 3.6, 4.5, 5.8 and 8.0{mu}m. The GLIMPSE combines the 3 surveys: * GLIMPSE-I covers the longitude ranges |l|=10--65{deg} and the latitude range |b|<=1{deg} (Benjamin et al. 2003PASP..115..953B) * GLIMPSE-II covers the longitude range of |l|<=10{deg}, and a latitude range |b|<=1{deg} from |l|=5--10, |b|<=1.5 for |l|=2--5, and |b|<=2{deg} for |l|<=2. GLIMPSE-II coverage excludes the Galactic center region |l|<=1, |b|<=0.75 observed by the GALCEN GO program (PID=3677). * GLIMPSE-3D adds vertical extensions up to |b|=4.2{deg} near the galactic center, and up to |b|=3{deg} in selected other parts of the Galaxy (+/-10, 18.5, 25, 30, and -15 (345){deg}). GLIMPSE-II had two-epoch coverage for a total of three visits on the sky. The observations consisted of two 1.2 second integrations at each position in the first epoch of data taking (September 2005) and a single 1.2 second integration at each position six months later (April 2006). The highly reliable v2.0 GLIMPSEII Catalog (v2.0_GLMIIC) consists of point sources that are detected at least twice in one band and at least once in an adjacent band and a S/N > 5 cut for the band with the two detections. There are also faint and bright flux limits on the Catalog entries. The more complete v2.0 Archive (v2.0_GLMIIA) has less stringent criteria, namely two detections in any bands, those detections having a S/N > 5. The IRAC data were bandmerged with the 2MASS All-Sky Point Source Catalog. See the GLIMPSEII v2.0 Data Products & Data Delivery document for more details. The catalog available from CDS merges the 3 surveys GLIMPSE-I (v2.0), GLIMPSE-II (v2.0), and GLIMPSE-3D; Catalog and Archive records are also merged here. In the regions of overlap between the 3 surveys (e.g. longitude around 10{deg}) preference was given to (1) GLIMPSE-II, as recommended in the GLIMPSE documents of May 2007 (glimpse1_v2.0.pdf) and April 2008 (glimpse2-v2.0.pdf); (2) GLIMPSE-I, and (3) GLIMPSE-3D sources. Sources from different surveys were merged if their position is closer than 0.1arcsec. Documents and a document describing in detail the point source photometry steps, see http://www.astro.wisc.edu/glimpse/docs.html
