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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

64 results found.

  1. LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
  2. LIGO/Virgo G268556: BSA radio observations at 110 MHz
  3. LIGO/Virgo G268556/GW170104: Konus-Wind observations
  4. LIGO/Virgo G268556: VERITAS Very-High-Energy Gamma-Ray Observations
  5. LIGO/Virgo G268556: Refined localization from CBC parameter estimation
  6. LIGO/Virgo G268556, G270580, G274296, and G275404: Konus-Wind observations
  7. LIGO/Virgo G268556: FLOYDS Spectrum of iPTF17cf/PS17fr Favors an AGN Classification
  8. LIGO/Virgo G268556: ANTARES upper limits
  9. LIGO/Virgo G268556/GW170104: MAXI/GSC observations
  10. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  11. LIGO/Virgo G268556: RATIR Observation of iPTF Candidates
  12. LIGO/Virgo G268556: Swift-XRT observations of iPTF17cw
  13. LIGO/Virgo G268556: spectra of two nuclear transients PS17fr and PS17er
  14. LIGO/Virgo G268556: TZAC TAROT network observations with TRE/TCA/TCH
  15. LIGO/Virgo G268556: Gemini spectra of Pan-STARRS1 transients
  16. LIGO/Virgo G268556: Early SWASP limits of ATLAS17aeu
  17. LIGO/Virgo G268556: Additional GROWTH follow up observation of iPTF Optical Transient Candidates
  18. LIGO/Virgo G268556: VLA follow-up of iPTF17cw
  19. LIGO/Virgo G268556/GW170104: Campo Imperatore Observatory observations
  20. LIGO/Virgo G268556: AMI 15 GHz detection of ATLAS17aeu
  21. LIGO/Virgo G268556: Swift/BAT data search
  22. LIGO/Virgo G268556: Lijiang Observatory GMG Telescope Upper Limit on ATLAS17aeu
  23. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF17bv and iPTF17ck
  24. LIGO/Virgo G268556: Spectroscopic observations of ATLAS17aeu and iPTF17cw
  25. LIGO/Virgo G268556: NOWT of EWE, Xinglong 0.6/0.9m, Xuyi 1m optical upper limits of ATLAS17aeu and a reminder of GCN 20394
  26. LIGO/Virgo G268556/GW170104: TNG observations of ATLAS17aeu
  27. LIGO/Virgo G268556: Swift-XRT confirms that ATLAS17aeu is fading in X-rays
  28. LIGO/Virgo G268556: ATLAS17aeu position is consistent with GRB170105A
  29. LIGO/Virgo G268556: Liverpool Telescope Spectroscopy of iPTF candidates
  30. LIGO/Virgo G268556: Pan-STARRS1 observations and summary of transient sources
  31. LIGO/Virgo G268556/GW170104: 10.4m GTC spectroscopic observations of iPTF17fs
  32. LIGO/Virgo G268556/GW170104: TNG spectroscopic observations of iPTF17ck and iPTF17dz
  33. LIGO/Virgo G268556: Gemini spectrum and Pan-STARRS observations of ATLAS17aeu
  34. LIGO/Virgo G268556: IPN Triangulation of GRB 170105A (association with ATLAS17aeu)
  35. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  36. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  37. LIGO/Virgo G268556: Continued iPTF Observations and Additional Optical Transient Candidates
  38. LIGO/Virgo G268556: Swift/UVOT observations of ATLAS17aeu
  39. LIGO/Virgo G268556: CALET Observations
  40. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  41. LIGO/Virgo G268556: VLA follow-up of ATLAS17aeu
  42. LIGO/Virgo G268556: AGILE-GRID preliminary analysis
  43. LIGO/Virgo G268556: EWE001 and EWE002- two events close to GCN 20382 with the skymap
  44. LIGO/Virgo G268556: Palomar 200-inch detects ATLAS17aeu, possible afterglow of GRB070105A?
  45. LIGO/Virgo G268556/GW170104: Global MASTER Net second OT detection
  46. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  47. LIGO/Virgo G268556: SWASP optical imaging
  48. LIGO/Virgo G268556/GW170104: Asiago Observations
  49. LIGO/Virgo G268556: Updated sky map from gravitational-wave data
  50. LIGO/Virgo G268556: HAWC follow-up of northern sky
  51. LIGO/Virgo G268556: Pan-STARRS1 observations of the skymap
  52. LIGO/Virgo G268556: ATLAS17aeu - an unusual transient within the skymap
  53. LIGO/Virgo G268556/GW170104: Global MASTER Net observations and first OT detection
  54. LIGO/Virgo G268556: ATLAS imaging of the skymap
  55. LIGO/Virgo G268556: DESGW/DECam observations
  56. LIGO/Virgo G268556: AGILE MCAL and Super-AGILE Observations
  57. LIGO/Virgo G268556: Fermi-LAT search for high-energy gamma-ray counterpart
  58. LIGO/Virgo G268556: Mini-MegaTORTORA follow-up observations
  59. LIGO/Virgo G268556: Swift-XRT sources
  60. LIGO/Virgo G268556: ANTARES search
  61. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  62. LIGO/Virgo G268556: INTEGRAL search of temporally coincident prompt hard X-ray emission
  63. LIGO/Virgo G268556: Fermi GBM Observations
  64. LIGO/Virgo G268556: Identification of a GW CBC Candidate

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