- ID:
- ivo://CDS.VizieR/J/AJ/148/124
- Title:
- Herschel key program Heritage
- Short Name:
- J/AJ/148/124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations from the HERschel Inventory of the Agents of Galaxy Evolution (HERITAGE) have been used to identify dusty populations of sources in the Large and Small Magellanic Clouds (LMC and SMC). We conducted the study using the HERITAGE catalogs of point sources available from the Herschel Science Center from both the Photodetector Array Camera and Spectrometer (PACS; 100 and 160{mu}m) and Spectral and Photometric Imaging Receiver (SPIRE; 250, 350, and 500{mu}m) cameras. These catalogs are matched to each other to create a Herschel band-merged catalog and then further matched to archival Spitzer IRAC and MIPS catalogs from the Spitzer Surveying the Agents of Galaxy Evolution (SAGE) and SAGE-SMC surveys to create single mid- to far-infrared (far-IR) point source catalogs that span the wavelength range from 3.6 to 500{mu}m. There are 35,322 unique sources in the LMC and 7503 in the SMC. To be bright in the FIR, a source must be very dusty, and so the sources in the HERITAGE catalogs represent the dustiest populations of sources. The brightest HERITAGE sources are dominated by young stellar objects (YSOs), and the dimmest by background galaxies. We identify the sources most likely to be background galaxies by first considering their morphology (distant galaxies are point-like at the resolution of Herschel) and then comparing the flux distribution to that of the Herschel Astrophysical Terahertz Large Area Survey (ATLAS) survey of galaxies. We find a total of 9745 background galaxy candidates in the LMC HERITAGE images and 5111 in the SMC images, in agreement with the number predicted by extrapolating from the ATLAS flux distribution. The majority of the Magellanic Cloud-residing sources are either very young, embedded forming stars or dusty clumps of the interstellar medium. Using the presence of 24{mu}m emission as a tracer of star formation, we identify 3518 YSO candidates in the LMC and 663 in the SMC. There are far fewer far-IR bright YSOs in the SMC than the LMC due to both the SMC's smaller size and its lower dust content. The YSO candidate lists may be contaminated at low flux levels by background galaxies, and so we differentiate between sources with a high ("probable") and moderate ("possible") likelihood of being a YSO. There are 2493/425 probable YSO candidates in the LMC/SMC. Approximately 73% of the Herschel YSO candidates are newly identified in the LMC, and 35% in the SMC. We further identify a small population of dusty objects in the late stages of stellar evolution including extreme and post-asymptotic giant branch, planetary nebulae, and supernova remnants. These populations are identified by matching the HERITAGE catalogs to lists of previously identified objects in the literature. Approximately half of the LMC sources and one quarter of the SMC sources are too faint to obtain accurate ample FIR photometry and are unclassified.
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- ID:
- ivo://CDS.VizieR/J/A+A/581/A30
- Title:
- Herschel maps of {rho} Oph
- Short Name:
- J/A+A/581/A30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of nearby star-forming regions with the Herschel Space Observatory complement our view of the protoplanetary disks in Ophiuchus with information about the outer disks. The main goal of this project is to provide new far-infrared fluxes for the known disks in the core region of Ophiuchus and to identify potential transitional disks using data from Herschel. We obtained PACS and SPIRE photometry of previously spectroscopically confirmed young stellar objects (YSO) in the region and analysed their spectral energy distributions.
- ID:
- ivo://CDS.VizieR/J/ApJ/759/139
- Title:
- Herschel + MIPS photometry of GOODS sources
- Short Name:
- J/ApJ/759/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the effects of active galactic nuclei (AGNs) and star formation activity on the infrared (0.3-1000{mu}m) spectral energy distributions (SEDs) of luminous infrared galaxies from z=0.5 to 4.0. We have compiled a large sample of 151 galaxies selected at 24{mu}m (S_24_>~100{mu}Jy) in the GOODS-N and ECDFS fields for which we have deep Spitzer IRS spectroscopy, allowing us to decompose the mid-IR spectrum into contributions from star formation and AGN activity. A significant portion (~25%) of our sample is dominated by an AGN (>50% of the mid-IR luminosity) in the mid-IR. Based on the mid-IR classification, we divide our full sample into four sub-samples: z~1 star-forming (SF) sources, z~2 SF sources, AGNs with clear 9.7{mu}m silicate absorption, and AGNs with featureless mid-IR spectra. From our large spectroscopic sample and wealth of multi-wavelength data, including deep Herschel imaging at 100, 160, 250, 350, and 500{mu}m, we use 95 galaxies with complete spectral coverage to create a composite SED for each sub-sample. We then fit a two-temperature component modified blackbody to the SEDs. We find that the IR SEDs have similar cold dust temperatures, regardless of the mid-IR power source, but display a marked difference in the warmer dust temperatures. We calculate the average effective temperature of the dust in each sub-sample and find a significant (~20K) difference between the SF and AGN systems. We compare our composite SEDs to local templates and find that local templates do not accurately reproduce the mid-IR features and dust temperatures of our high-redshift systems. High-redshift IR luminous galaxies contain significantly more cool dust than their local counterparts. We find that a full suite of photometry spanning the IR peak is necessary to accurately account for the dominant dust temperature components in high-redshift IR luminous galaxies.
- ID:
- ivo://CDS.VizieR/VIII/95
- Title:
- Herschel Multi-tiered Extragalactic Survey
- Short Name:
- VIII/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy programme designed to map a set of nested fields totalling ~380deg^2^. Fields range in size from 0.01 to ~20deg^2^, using the Herschel-Spectral and Photometric Imaging Receiver (SPIRE) (at 250, 350 and 500um) and the Herschel-Photodetector Array Camera and Spectrometer (PACS) (at 100 and 160um), with an additional wider component of 270deg^2^ with SPIRE alone. These bands cover the peak of the redshifted thermal spectral energy distribution from interstellar dust and thus capture the reprocessed optical and ultraviolet radiation from star formation that has been absorbed by dust, and are critical for forming a complete multiwavelength understanding of galaxy formation and evolution.
- ID:
- ivo://CDS.VizieR/VIII/103
- Title:
- Herschel Multi-tiered Extragalactic Survey
- Short Name:
- VIII/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HerMES is the Herschel Multi-tiered Extragalactic Survey, an astronomical project to study the evolution of galaxies in the distant Universe.It is the largest project on ESA's Herschel Space Observatory (900 hours). You will find more information about it on the HerMES website (http://hedam.lam.fr/HerMES/). The project is carried out by a large team, made up primarily of people who built one of the instruments on Herschel called SPIRE.
- ID:
- ivo://CDS.VizieR/J/ApJ/753/147
- Title:
- Herschel observations stars in THA
- Short Name:
- J/ApJ/753/147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Herschel PACS photometry of 17 B- to M-type stars in the 30Myr old Tucana-Horologium Association. This work is part of the Herschel Open Time Key Programme "Gas in Protoplanetary Systems" (GASPS). 6 of the 17 targets were found to have infrared excesses significantly greater than the expected stellar IR fluxes, including a previously unknown disk around HD30051. These six debris disks were fitted with single-temperature blackbody models to estimate the temperatures and abundances of the dust in the systems. For the five stars that show excess emission in the Herschel PACS photometry and also have Spitzer IRS spectra, we fit the data with models of optically thin debris disks with realistic grain properties in order to better estimate the disk parameters. The model is determined by a set of six parameters: surface density index, grain size distribution index, minimum and maximum grain sizes, and the inner and outer radii of the disk. The best-fitting parameters give us constraints on the geometry of the dust in these systems, as well as lower limits to the total dust masses. The HD105 disk was further constrained by fitting marginally resolved PACS 70{mu}m imaging.
- ID:
- ivo://CDS.VizieR/J/ApJS/222/16
- Title:
- Herschel obs. of major-merger pairs of z<0.1 galaxies
- Short Name:
- J/ApJS/222/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Herschel PACS and SPIRE far-infrared (FIR) and submillimeter imaging observations for a large K-band selected sample of 88 close major-merger pairs of galaxies (H-KPAIRs) in 6 photometric bands (70, 100, 160, 250, 350, and 500{mu}m). Among 132 spiral galaxies in the 44 spiral-spiral (S+S) pairs and 44 spiral-elliptical (S+E) pairs, 113 are detected in at least 1 Herschel band. The star formation rate (SFR) and dust mass (M_dust_) are derived from the IR SED fitting. The mass of total gas (M_gas_) is estimated by assuming a constant dust-to-gas mass ratio of 0.01. Star-forming spiral galaxies (SFGs) in S+S pairs show significant enhancements in both specific star formation rate (sSFR) and star formation efficiency (SFE), while having nearly the same gas mass compared to control galaxies. On the other hand, for SFGs in S+E pairs, there is no significant sSFR enhancement and the mean SFE enhancement is significantly lower than that of SFGs in S+S pairs. This suggests an important role for the disk-disk collision in the interaction-induced star formation. The M_gas_ of SFGs in S+E pairs is marginally lower than that of their counterparts in both S+S pairs and the control sample. Paired galaxies with and without interaction signs do not differ significantly in their mean sSFR and SFE. As found in previous works, this much larger sample confirms that the primary and secondary spirals in S+S pairs follow a Holmberg effect correlation on sSFR.
- ID:
- ivo://CDS.VizieR/J/ApJ/863/13
- Title:
- Herschel obs. of protoplanetary disks in L1641
- Short Name:
- J/ApJ/863/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze Herschel Space Observatory observations of 104 young stellar objects with protoplanetary disks in the ~1.5Myr star-forming region Lynds 1641 (L1641) within the Orion A Molecular Cloud. We present spectral energy distributions from the optical to the far-infrared including new photometry from the Herschel Photodetector Array Camera and Spectrometer at 70{mu}m. Our sample, taken as part of the Herschel Orion Protostar Survey, contains 24 transitional disks, 8 of which we identify for the first time in this work. We analyze the full disks (FDs) with irradiated accretion disk models to infer dust settling properties. Using forward modeling to reproduce the observed n_Ks-[70]_ index for the FD sample, we find the observed disk indices are consistent with models that have depletion of dust in the upper layers of the disk relative to the midplane, indicating significant dust settling. We perform the same analysis on FDs in Taurus with Herschel data and find that Taurus is slightly more evolved, although both samples show signs of dust settling. These results add to the growing literature that significant dust evolution can occur in disks by ~1.5Myr.
- ID:
- ivo://CDS.VizieR/J/PASJ/71/13
- Title:
- Herschel-PACS North Ecliptic Pole Survey
- Short Name:
- J/PASJ/71/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A detailed analysis of Herschel-PACS observations at the North Ecliptic Pole has been made. High quality maps, covering an area of 0.44 square degrees, are produced and then used to derive new candidate source lists. A rigorous quality control pipeline has been used to create final legacy catalogues in the PACS Green 100um and Red 160um bands, containing 1385 and 630 sources respectively. These catalogues reach to more than twice the depth of the current archival Herschel/PACS Point Source Catalogue detecting 401 and 270 more sources in the short and long wavelength bands respectively. These counts have been used to construct galaxy source counts that extend down to flux densities of 6mJy and 19mJy (50% completeness) in the Green 100 micron and Red 160 micron bands respectively. These source counts are consistent with previously published PACS number counts in other fields across the sky. The source counts have been compared with galaxy evolution models identifying a population of luminous infrared galaxies as responsible for the bulk of the galaxy evolution over the flux range (5-100mJy) spanned by the observed counts, contributing approximate fractions of 50% and 60% to the cosmic infrared background (CIRB) at 100um and 160um respectively.
- ID:
- ivo://CDS.VizieR/VIII/106
- Title:
- Herschel/PACS Point Source Catalogs
- Short Name:
- VIII/106
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The Herschel Space Observatory was the fourth cornerstone mission in the European Space Agency (ESA) science programme. It had excellent broad band imaging capabilities in the far-infrared (FIR) and sub-millimetre part of the electromagnetic spectrum. Although the spacecraft finished observing in 2013, it left a large legacy dataset that is far from having been fully explored and still has a great potential for new scientific discoveries. The PACS and SPIRE photometric cameras observed about 8% of the sky in six different wavebands. This document describes the Herschel/PACS Point Source Catalogue (HPPSC), a FIR catalogue based on the broad-band photometric observations of the PACS instrument with filters centred at 70, 100 and 160um. We analysed all combined, Level 2.5/Level 3 Herschel/PACS photometric observations including 682 Parallel Mode, 12932 nominal mode and 1644 SSO maps. The PACS photometer maps that we produced were generated by applying the JScanam task of the Herschel Interactive Processing Environment (HIPE) v13.0.0. Sources were identified with the HIPE implementation of SUSSEXtractor, and the flux densities obtained by aperture photometry. We found a total of 108319 point sources that are considered to be reliable in the 70um maps, 131322 at 100um and 251392 point sources in the 160um maps. In addition, our quality control algorithm identified 546587 candidate sources that were found to be extended and 7185160 features which did not pass the signal-to-noise and other criteria to be considered reliable sources. These sources were included in the Extended Source List and Rejected Source List of the HPPSC, respectively. The calculated completeness and photometric accuracy values are based on simulations, where artificial sources were injected into the observational timeline with well controlled flux density values. The actual completeness is a complex function of the source flux, photometric band and the background complexity.