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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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.

Advanced Search Examples (click to copy):

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

7455 results found.

  1. Fermi GBM-190816+LIGO/Virgo : no neutrino counterpart candidate in ANTARES search
  2. Fermi GBM-190816: A subthreshold GRB candidate potentially associated with a subthreshold LIGO/Virgo compact binary merger candidate
  3. IceCube-190819A: Upper limits from Fermi-GBM Observations
  4. IceCube-190819A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  5. IceCube-190819A - IceCube observation of a high-energy neutrino candidate event
  6. LIGO/Virgo S190814bv: GRAWITA TNG NIR imaging of AT2019nqq and AT2019nqc
  7. LIGO/Virgo S190814bv: DESGW candidate update
  8. LIGO/VIRGO S190814bv: AbAO non-detection of AT2019nme
  9. LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  10. LIGO/Virgo S190814bv: Not observable by CALET
  11. LIGO/Virgo S190814bv: Pan-STARRS imaging indicates DG19sevhc (AT2019npy) is a proper motion star
  12. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  13. LIGO/Virgo S190814bv: No additional candidates from the Zwicky Transient Facility
  14. LIGO/Virgo S190814bv: SOAR spectroscopy of 2 DESGW candidates
  15. LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
  16. LIGO/Virgo S190814bv: No candidates from DCT galaxy targeted search and observations of DECam-GROWTH candidates
  17. LIGO/Virgo S190814bv: New candidates from DECam DESGW difference imaging search
  18. LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
  19. S190814bv: MASTER analysis of DECam-GROWTH candidates
  20. LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
  21. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  22. LIGO/Virgo S190814bv: No candidates identified in DECam data by visual inspection
  23. LIGO/Virgo S190814bv: des-gw190814b is a moving object
  24. LIGO/Virgo S190814bv: ATLAS forced photometry non-detections of DESGW candidates
  25. LIGO/Virgo S190814bv: No candidates from the Zwicky Transient Facility
  26. LIGO/Virgo S190814bv: KMTNet observation
  27. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  28. LIGO/Virgo S190814bv: Candidates found in initial DESGW search
  29. LIGO/Virgo S190814bv: Upper limits from AGILE-GRID observations
  30. LIGO/Virgo S190814bv: Update on Sky-Localization and Source-Classification
  31. LIGO/Virgo S190814bv: no candidates from WHT imaging of candidate galaxies
  32. LIGO/Virgo S190814bv: GRAWITA TNG imaging of selected galaxies
  33. LIGO/Virgo S190814bv : no neutrino counterpart candidate in ANTARES search
  34. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  35. LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
  36. LIGO/Virgo S190814bv: Identification of a GW compact binary merger candidate
  37. LIGO/Virgo S190814bv: Upper limits from IceCube neutrino searches
  38. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  39. HAWC-190806A: Swift-XRT observations
  40. Trigger_11505: Tiled Swift observations
  41. LIGO/Virgo S190728q: New optical candidates from the DESGW program
  42. LIGO/Virgo S190808ae: Retraction of GW compact binary merger candidate
  43. LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
  44. LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
  45. LIGO/Virgo S190808ae: One Coincident Neutrino Candidate from IceCube Search
  46. LIGO/Virgo S190808ae: Identification of a GW compact binary merger candidate
  47. GRB 190805B: Tiled Swift observations
  48. GRB 190804B: Tiled Swift observations
  49. IceCube 190730A: No counterpart candidates or blazar activity in GOTO observations
  50. GRB 190719C: VLT/X-shooter spectroscopic redshift of the host galaxy
  51. LIGO/Virgo S190727h: Updated sky localization
  52. GRB 190731A: Swift ToO observations
  53. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
  54. IceCube 190730A: not observable by Fermi-GBM
  55. LIGO/Virgo S190707q: AstroSat CZTI upper limits
  56. LIGO/Virgo S190718y: AstroSat CZTI upper limits
  57. LIGO/Virgo S190727h: AstroSat CZTI upper limits
  58. LIGO/Virgo S190720a: AstroSat CZTI upper limits
  59. IceCube-190730A - IceCube observation of a high-energy neutrino candidate event
  60. LIGO/Virgo S190727h: Gaia Photometric Alerts transient candidate
  61. LIGO/Virgo S190728q/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
  62. LIGO/VIRGO S190728q: No candidate counterparts from ATLAS observations
  63. LIGO/Virgo S190728q: Third update on neutrino search with IceCube
  64. LIGO/Virgo S190728q: Update on Sky-Localization and Source-Classification
  65. LIGO/Virgo S190728q: ZTF19abjethn is inconsistent with new GW localization
  66. LIGO/Virgo S190728q: Identification of a Faint Blue Static Source at the Location of ZTF19abjethn
  67. LIGO/Virgo S190728q: Photometric Redshift and Stellar Mass Estimates for the Potential Host Galaxy of Optical Counterpart Candidate ZTF19abjethn
  68. LIGO/Virgo S190728q: Optical Candidate from the Zwicky Transient Facility ZTF19abjethn
  69. LIGO/Virgo S190728q: Second update on neutrino search with IceCube
  70. LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
  71. LIGO/Virgo S190728q: no counterpart candidates in AGILE-GRID observations
  72. LIGO/Virgo S190728q : no neutrino counterpart candidate in ANTARES search
  73. LIGO/Virgo S190728q: One neutrino candidate from IceCube search
  74. LIGO/Virgo S190728q: No counterpart candidates in HAWC observations
  75. LIGO/Virgo S190728q: Identification of a GW compact binary merger candidate
  76. LIGO/Virgo S190728q: Upper limits from IceCube neutrino searches
  77. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  78. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  79. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  80. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  81. LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
  82. LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
  83. LIGO/Virgo S190727h: Upper limits from IceCube neutrino searches
  84. LIGO/Virgo S190718y: Gaia Photometric Alerts transient candidates
  85. LIGO/Virgo S190720a: Updated localization from LIGO and Virgo data
  86. LIGO/Virgo S190720a: Upper limits from CALET observations
  87. GRB 190719C: Swift/UVOT Upper Limits
  88. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  89. LIGO/Virgo S190720a: Upper limits from AGILE-GRID observations
  90. LIGO/Virgo S190720a : no neutrino counterpart candidate in ANTARES search
  91. LIGO/Virgo S190720a: AGILE-MCAL observations
  92. LIGO/Virgo S190720a: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo S190720a: No counterpart candidates in HAWC observations
  94. LIGO/Virgo S190720a: Upper limits from IceCube neutrino searches
  95. GRB 190719C: NOT candidate optical afterglow and host
  96. LIGO/Virgo S190718y: ZTF pre-detection of MASTER candidate AT2019lly
  97. LIGO/Virgo S190718y: Analysis update
  98. GRB 190719C: Swift detection of a burst
  99. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  100. LIGO/Virgo S190630ag: Updated sky localization

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