Swift-XRT Survey of Fermi Unassociated Sources


These results are part of the Swift program to follow-up Fermi unassociated sources in an attempt to find X-ray counterparts to the unidentified gamma-ray sources. As new observations are performed, these pages will be updated in nearly real time. Please use these results as a guide and proceed with caution when using them in a publication since they are the result of an automated analysis.

When using these data and results in publications, please reference M.C. Stroh & A.D. Falcone 2013, ApJS, 207, 28; arXiv: 1305.4949 for a description of many of the analysis techniques used to reduce these data (note: a more detailed paper describing the complete data set and analysis is forthcoming). Please contact Abe Falcone and Michael Stroh at unassociated@swift.psu.edu if you have any questions about the program or the analysis, or to simply to let us know that you've made use of these data.


Caution: For completeness, sources are listed if the "detection" exceeds 3 sigma. The significances and images are shown so you can make more stringent significance cuts, if desired.

4FGL J1818.5+2533

Field

Detected Excesses

Swift-XRT image of the field for 4FGL J1818.5+2533 Swift-XRT detections in the field for 4FGL J1818.5+2533

Detected Excesses (SNR(Sosta) > 3.0)

# R.A. (J2000) Dec. (J2000) Pos. Error (") Rate (cts/s) Counts SNR (Detect) SNR (Sosta)
1 18 18 30.88 +25 37 03.71 5.35 (4.2 ± 0.9) x 10-3 30 4.584 4.483
2 18 18 43.86 +25 25 14.47 6.04 (2.9 ± 0.8) x 10-3 19 3.851 3.611

Rejected Excesses (Due to Overlaps or SNR(Sosta) < 3.0)

# R.A. (J2000) Dec. (J2000) Pos. Error (") Rate (cts/s) Counts SNR (Detect) SNR (Sosta)
1 18 18 06.18 +25 35 59.16 6.31 (1.7 ± 0.6) x 10-3 14 2.928 2.827
2 18 19 04.10 +25 27 58.14 6.21 (1.2 ± 0.5) x 10-3 11 2.373 2.347

X-Ray and Gamma Ray Catalogs

More Catalogs

Swift-XRT image with known X-ray and gamma ray sources for 4FGL J1818.5+2533 Swift-XRT image with known radio, optical and UV sources for 4FGL J1818.5+2533


No known X-ray or gamma ray sources found.

Known Radio, Optical and UV Sources

# Source Name R.A. (J2000) Dec. (J2000) Offset (') Database Table
1 NVSS J181846+252852 18 18 46.30 +25 28 51.96 5.16 NVSS
2 HD 335946 18 18 42.53 +25 38 37.68 5.48 HDEC
3 NVSS J181902+253148 18 19 02.21 +25 31 48.00 6.26 NVSS
TGSSADR J181902.1+253143 18 19 02.11 +25 31 42.96 6.27 GMRTAS150M
4 BD+25 3485 18 18 45.48 +25 26 50.64 6.94 ACRS
PPM 107054 18 18 45.48 +25 26 49.92 6.95 PPM
HD 335953 18 18 45.48 +25 26 49.92 6.95 HDEC
SAO 85913 18 18 45.62 +25 26 49.92 6.97 SAO
5 NVSS J181805+253548 18 18 06.00 +25 35 48.12 7.05 NVSS
6 NVSS J181900+253906 18 19 00.29 +25 39 06.84 8.03 NVSS
7 NVSS J181857+252631 18 18 57.79 +25 26 30.84 8.55 NVSS
8 NVSS J181916+252949 18 19 16.20 +25 29 48.84 9.89 NVSS
QORG J181920.6+253303 18 19 20.59 +25 33 02.88 10.22 QORGCAT
9 NVSS J181824+252324 18 18 24.91 +25 23 25.08 10.26 NVSS
10 NVSS J181920+253302 18 19 20.90 +25 33 02.16 10.29 NVSS
11 HD 335852 18 17 45.46 +25 35 08.16 11.38 HDEC
12 WDS J18180+2525 18 18 00.00 +25 25 00.12 11.58 WDS
13 WDS J18192+2525 18 19 12.00 +25 25 00.12 11.79 WDS
14 HD 335861 18 17 57.12 +25 25 07.68 11.95 HDEC
15 NVSS J181922+252729 18 19 22.90 +25 27 29.16 12.26 NVSS
16 NVSS J181925+252623 18 19 25.10 +25 26 22.92 13.24 NVSS
17 NVSS J181915+252334 18 19 15.19 +25 23 34.08 13.32 NVSS
18 HD 335952 A 18 19 24.29 +25 23 59.64 14.51 HDEC
19 PGC 1735219 18 17 45.50 +25 24 06.84 14.58 PGC2003
HD 335952 B 18 19 24.70 +25 23 40.92 14.78 HDEC

Penn State University Goddard Space Flight Center Swift