The SPIRE Point Source Catalog (SPSC) Status Bernhard Schulz on behalf of the SPSC Team NHSC-IPAC Caltech

The SPSC Team NASA Herschel Science Center IPAC-Caltech Nanyao Lu John Rector Bernhard Schulz (PI) David Shupe Kevin Xu Konkoly Observatory Csaba Kiss Gabor Marton Erika Varga-Verebélyi SPIRE ICC, Rutherford Appleton Labs, STFC Chris Pearson SPIRE ICC, Cardiff University Andreas Papageorgiou Herschel Science Centre, ESAC-ESA Tanya Lim Ivan Valtchanov Eötvös Loránd University Budapest Sándor Pintér Victor Tóth

SPIRE Scan Map Observations 6917 Scan Map Obs. Total 4204 Small Scan Obs. 1880 Large Scan Map Obs. 833 Parallel Mode Obs. Red: Single Maps Green: Galactic Plane overlapping maps Blue: Other overlapping maps

Catalog Consolidation Building the SPSC Re-Processing TwoPass Pipeline Incl. Turn-around data HSA SpireCat Postgres database SPSC Re-Processing Local Pool Source Extraction STRN Map generation Structure Noise Maps Catalog Consolidation Source Extraction Detection Photometry Determine source extension Pointing correction Catalog Consolidation Resolve source multiplicities Error analysis Catalog statistics Flags Local STRN extraction

Daophot Parameter Filter Source Detection point source map ext. source map Start Level 1 context Sussextractor Daophot Daophot Parameter Filter Timeline Fitter Fixed Timeline Fitter Free Output Table End

Structure Noise Calculation The Lockman Hole (KPGT_dlutz_1) Field G334.65+2.67 (KPOT_mjuvela_1) The structure noise measures the fluctuation around a given point in the sky. This measure can be translated into the power spectrum of the neighbouring areas, but it gives local information instead of a general number. We use this quantity to describe the background noise in the close vicinity of each detected source. For each pixel of the map the structure noise (NS) is calculated as the mean deviation of the pixel’s (green) flux with respect to the reference pixel (red). It is calculated as follows: , where and μ is the mean value of the di values.

SPSC Status 1 Data Reprocessing Pointing Source Extraction Small and large scan maps complete since June 2015. Parallel mode maps complete since Sept 2015. Very few maps resisted reprocessing and are excluded for now. Pointing Corrections available for more than 1/3 of all maps from WISE catalog stacking. Most observations have good pointing accuracy for SPIRE except a few due to Star Tracker issues. Focus on combined maps that are destriped together. Source Extraction First test of production grade point source extraction procedure in August 2015. Small and large scan maps  2.5 M source candidates in Sept 2015. All combined maps (parallel and large)  5.7 M source candidates in Oct 2015. All 8.2M source candidates ingested in relational Postgres database.

Database Schema (SpireCat) Observation Table (observation) Obs ID: Primary Key List of all scan map observations Source Table (source) Source ID: Primary Key Obs ID: Foreign Key Group ID: Foreign Key List of source detections with different algorithms Catalog (catalog) Group ID: Primary Key List of groups of source detections belonging to the same source Position Corrections (poscorr) List of position offsets from WISE point source stacking Large Galaxies (largegal) Galaxy ID: Primary Key List of encircling ellipses of galaxies >1’ from 2MASS Catalog SSO Tracks SSO ID: Primary Key List of start and end positions and estimated fluxes in SPIRE filters Structure Noise Table (strn) List of structure noise numbers for each source position in SPIRE filters linked by position Postgres database with fast Q3C position indexing. Relational Postgres database Run Log (runlog) (ObsID, SwVersion): Primary Key Information about source extraction runs safeguarding ingestion into source table. WISE W4 Sources (wisecat) name: Primary Key Catalog of WISE 22 mm sources with S/N>=3 and w4m>1 to support position corrections through stacking. linked by Source ID linked by Obs ID and Sw Version position Obs ID linked by Group ID

SPSC Status 2 Uncertainties Quality Control Structure noise maps were produced for all observations that have reprocessed maps and the list of specific values for each position is in the making. Photometric accuracy, and completeness expressed as a function of structure noise still needs to be fully established through simulations by source injection. Quality Control Sources where positions of both timeline fits disagree with the Sussextractor position are flagged. Sources where photometry substantially disagrees between methods are flagged. A tool was developed that shows cutouts of maps around source detections from a source list. Various statistics will be derived from the database to find parameters like semi-extended source thresholds etc.

Catalog Entries ObsID Cross Reference Object ID Array Name RA DEC s D RA D DEC Position Errors Offsets l Position Information Source ID Object ID Observ. ID unique Flags Extended Source SSO Contamination Map Edge Large Galaxy Variability STRN Category Cirrus Category ? Catalog entries aim to provide the best position and flux values for a given object, based on the source extractions from one or several observations (maps). Flux s Instr. N of M Det. M Det. Flags Quality Noise # of detections Flux Information Quality Info

SPSC Status 3 Additional Data for Flags Catalog Consolidation A list of nearby galaxies supplied by NED will be used to flag sources within these regions. A list with tracks of known Solar System Objects in the SPIRE maps will be used to flag potential conflicts. The structure noise category will be set based on the corresponding table. The other planned flags will be derived from local information. Catalog Consolidation Currently we focus on the CCDPs. The first procedure that creates the catalog entries by linking all source detections indistinguishable by position and wavelength, has been tested successfully. A first catalog of the representative dataset sources (~170000) was created as a test bed for those CCDPs that fill the rest of the catalog columns. A first skeleton catalog was produced end of 2015 with (2.8, 2.1, 0.8)M objects/groups for 250, 350, 500 micron respectively. Documentation Initial documents were SPSC Implementation Plan and the SPSC Feasibility Study. We produced and are maintaining the SPSC Work-Packages Document and the SPSC Database Primer, that contain most information relevant to the project at this time. Final documentation will be in form of an Explanatory Supplement and a refereed paper.

Remaining Issues Pointing Extended source discrimination Only about one third of the corrections from WISE stacking are reliable so far. Extended source discrimination Investigation using machine learning for source classification Combined Observations There are many shallow Level 2 maps that overlap, that would provide better and more reliable source detections if combined first as Level 2.5. Some naming inconsistencies exist that need fixing. Old HIPE 13 and 14 bugs Reprocessing was performed using HIPE 12.1 processed Level 0 data with HIPE 13.0.5130 and for some combined maps with HIPE 14.0.2939. A number of issues were fixed and deglitching and destriping were improved in HIPE 14 RC2. Catalog Column Derivation Procedures Taking more time to develop.

Conclusion We have generated a first skeleton catalog. Working on CCDPs for catalog columns and quality assessment. First catalog version expected spring 2016. Consider splitting into high quality catalog for science use and source list with lower photometric accuracy for obs. planning. Some quality issues regarding pointing, and source extraction can only be fixed in a second round.

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Appendix

Coverage Estimates SPIRE observed a total area of 4723 deg^2 equivalent to ~11.4% of the sky. Back-of-the-spreadsheet-calculation! Duplicate coverage was only corrected for considering parallel mode. Included increase over nominal areas. Include turnaround data. Removing turnaround data will decrease the covered area to ~10.8% of the sky. Depending on the detection threshold we can expect a total of about 3 Million sources in all three bands for a 30 mJy threshold. All scan maps squ. deg   fraction of all sky Total 4723 11.4% SpirePacsParallel 2515 53% 6.1% SpirePhotoLargeScan 2001 42% 4.8% SpirePhotoSmallScan 208 4% 0.5% Without Calibration squ. deg # diff fraction of all sky Total 4516 208 96% 10.9% Parallel Mode 2439 76 54% 5.9% Large Map 1899 102 42% 4.6% SmallMap   178 30 4% 0.4% Especially the Galactic Plane will make point source detection and discrimination very difficult. Excluding +/- 2 deg around the Galactic Plane will reduce the area coverage by ~20%. Exclude Galactic Plane   of all SPIRE GalLat thresh. [deg] 2 # diff fraction of all sky Total 3650 866 81% 8.8% Parallel Mode 1598 841 44% 3.9% Large Map 1882 17 52% 4.6% SmallMap 170 8 5% 0.4%

Optimal Timeline Fitter Parameters Core Area Background Annulus Timeline Fitter set to use readouts from central region and background annulus to fit Gaussian PSF model. Allow background level to vary. Choose annulus to begin after 2nd Airy ring and cover area only slightly larger than core area. In second run allow elliptical fit and tilted background to distinguish extended sources. PSW PMW PLW Core radius [“] 22 30 42 Inner radius [“] 70 98 140 Outer radius [“] 74 103 147 PSF Core Area Background Annulus

Source Extraction Parameters PSW PMW PLW Sussex-tractor Daophot Timeline Fitter Remarks fwhm 17.6 23.9 35.2 x FWHM in arcsec pixSize 6 10 14 N/A Pixel size in arcsec detThreshold 3 S/N detection threshold rpeak 22 30 42 Radius of central source aperture in arcsec prfSize 5 Size of Sussextractor PRF in pixels innerArcsec Inner radius of background annulus in arcsec outerArcsec 33 45 63 Outer radius of background annulus in arcsec maxIter 400 Maximum number of iterations rBackground[0] 70 98 140 rBackground[1] 74 103 147

Source Extraction per ObsID (spscRunObsid.py) Start Load next Observation PNG Map Overplots Post Processing Source Table Run Table End Level 2.5 exists? yes no Combine Level 1 scans Copy maps from L2.5 Copy maps from L2 Copy Level 1 scans point source maps ext. source maps Level 1 scans Source Extractor List of linked observations First ObsID? ObsID List End of List?

Source Extractor (spscExtract.py) source list 1 TL Fixed Par. point source map ext. source map Start Level 1 context Sussextractor Daophot Daophot Param. Daophot Parameter Filter source list 2 Timeline Fitter Fixed Timeline Fitter Free TL Free Par. Output Table End