ACTSSRCAT - Atacama Cosmology Telescope 2008 Southern Survey 148/218 GHz Source Catalog

Overview

This table contains a catalog of 191 extragalactic sources detected by the Atacama Cosmology Telescope (ACT) at 148 and/or 218 GHz in the 2008 Southern survey. Flux densities span 14 -1700 mJy, and the authors use source spectral indices derived using ACT-only data to divide their sources into two subpopulations: 167 radio galaxies powered by central active galactic nuclei (AGN) and 24 dusty star-forming galaxies (DSFGs). They cross-identify 97% of their sources (166 of the AGN and 19 of the DSFGs) with those in currently available catalogs. When combined with flux densities from the Australia Telescope 20-GHz survey and follow-up observations with the Australia Telescope Compact Array, the synchrotron-dominated population is seen to exhibit a steepening of the slope of the spectral energy distribution from 20 to 148 GHz, with the trend continuing to 218 GHz. The ACT dust-dominated source population has a median spectral index, alpha_148-218GHz, of 3.7^+0.62_-0.86, and includes both local galaxies and sources with redshift around 6. Dusty sources with no counterpart in existing catalogs likely belong to a recently discovered subpopulation of DSFGs lensed by foreground galaxies or galaxy groups.

The ACT experiment (Swetz et al., 2011, ApJS, 194, 41) is situated on the slopes of Cerro Toco in the Atacama Desert of Chile at an elevation of 5190m. ACT's latitude gives access to both the northern and southern celestial hemispheres. Observations occurred simultaneously in three frequency bands, at 148 GHz (2.0 mm), 218 GHz (1.4 mm) and 277 GHz (1.1 mm) with angular resolutions of roughly 1.4, 1.0 and 0.9 arcminutes, respectively.

The ACT-detected source list contains 169 sources selected at 148 GHz with S/N > 5, spanning two decades in flux density, from 14 to 1700 mJy. The 218 GHz map independently yielded 133 sources with S/N > 5. The combination of these two independent source lists from which the present table was constructed gives a total count of 191 sources, with 110 galaxies detected with S/N > 5 at both frequencies.

Catalog Bibcode

2014MNRAS.439.1556M

References

The Atacama Cosmology Telescope: dusty star-forming galaxies and active
galactic nuclei in the Southern survey.
    Marsden D., Gralla M., Marriage T.A., Switzer E.R., Partridge B.,
    Massardi M., Morales G., Addison G., Bond J.R., Crichton D., Das S.,
    Devlin M., Dunner R., Hajian A., Hilton M., Hincks A., Hughes J.P.,
    Irwin K., Kosowsky A., Menanteau F., Moodley K., Niemack M., Page L.,
    Reese E.D., Schmitt B., Sehgal N., Sievers J., Staggs S., Swetz D.,
    Thornton R., Wollack E.
   <Mon. Not. R. Astron. Soc., 439, 1556-1574 (2014)>
   =2014MNRAS.439.1556M

Provenance

This table was created by the HEASARC in May 2015 based on CDS Catalog J/MNRAS/439/1556/ file table4.dat.

Parameters

Name
The ACT-S J2000.0 position-based source designation ('ACT-S JHHMMSS+DDMMSS') in the style registered with the Dictionary of Nomenclature of Celestial Objects.

Source_Flag
This source flag parameter is set to 'd' if the ACT source is not cross-identified with the catalogs specified in Section 5 of the reference paper.

RA
The Right Ascension of the ACT source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.1 seconds of time in the original reference table.

Dec
The Declination of the ACT source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.1 arcseconds in the original reference table.

LII
The Galactic Longitude of the ACT source.

BII
The Galactic Latitude of the ACT source.

SNR_148_GHz
The signal-to-noise ratio of the ACT source detection at 148 GHz.

Meas_Flux_148_GHz
The 'raw' flux density of the ACT source as estimated directly from the ACT 148-GHz map, as described in Section 3 of the reference paper, in mJy.

Flux_148_GHz
The deboosted flux density of the ACT source at 148 GHz, in mJy, derived according to Section 4.2 of the reference paper.

Flux_148_GHz_Pos_Err
The 68%-confidence positive error in the deboosted flux density of the ACT source at 148 GHz, in mJy.

Flux_148_GHz_Neg_Err
The 68%-confidence negative error in the deboosted flux density of the ACT source at 148 GHz, in mJy.

SNR_218_GHz
The signal-to-noise ratio of the ACT source detection at 218 GHz.

Meas_Flux_218_GHz
The 'raw' flux density of the ACT source as estimated directly from the ACT 218-GHz map, as described in Section 3 of the reference paper, in mJy.

Flux_218_GHz
The deboosted flux density of the ACT source at 218 GHz, in mJy, derived according to Section 4.2 of the reference paper.

Flux_218_GHz_Pos_Err
The 68%-confidence positive error in the deboosted flux density of the ACT source at 218 GHz, in mJy.

Flux_218_GHz_Neg_Err
The 68%-confidence negative error in the deboosted flux density of the ACT source at 218 GHz, in mJy.

Meas_Spectral_Index
The raw spectral index alpha (where S_nu ~ nu^alpha) of the ACT source between 148 and 218 GHz calculated using the meas_flux_148_ghz and meas_flux_218_ghz parameter values.

Spectral_Index
The deboosted spectral index alpha (where S_nu ~ nu^alpha) of the ACT source between 148 and 218 GHz calculated using the flux_148_ghz and flux_218_ghz parameter values.

Spectral_Index_Pos_Err
The positive error in the deboosted spectral index alpha of the ACT source between 148 and 218 GHz.

Spectral_Index_Neg_Err
The negative error in the deboosted spectral index alpha of the ACT source between 148 and 218 GHz.

Source_Class
The classification of the ACT source according to the spectral index criterion described in section 4.2 of the reference paper, viz:

    Sync = synchrotron-dominated sources (the vast majority of which are
           cross-identified with radio catalogs)

    Dust = low-redshift dust-dominated sources with IRAS counterparts
           (typically ULIRGs) and dust-dominated sources also observed by
  	 the South Pole Telescope (SPT), or with no cross-identification,
  	 either shown or assumed to be high-redshift star-forming galaxies.

AT20G_Name
The AT20G designation of the 20-GHz counterpart to the ACT source, if present in the AT20G catalog, e.g., 'AT20G J001849-511455', or the name of the 20-GHz source counterpart in the 2010 November ATCA follow-up observations made by the authors (if at20g_flag = 'f'), e.g., 'AT20G-f J064150-555103' (this latter naming convention was created by the HEASARC, notice, and is unofficial). This field is left blank if there is no known 20-GHz counterpart.

AT20G_Flag
This flag parameter is set to 'f' to indicate that the 20-GHz counterpart is from the 2010 November ATCA follow-up observations made by the authors.

Flux_20_GHz
The flux density of the 20-GHz counterpart to the ACT source, in mJy.

Flux_20_GHz_Error
The uncertainty in the flux density of the 20-GHz counterpart to the ACT source, in mJy.

Contact Person

Questions regarding the ACTSSRCAT database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:24:04 EDT