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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').
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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"

8524 results found.

  1. IceCube-190819A - IceCube observation of a high-energy neutrino candidate event
  2. LIGO/Virgo S190814bv: GRAWITA TNG NIR imaging of AT2019nqq and AT2019nqc
  3. LIGO/Virgo S190814bv: DESGW candidate update
  4. LIGO/Virgo S190814bv: DG19dnjlc is not offset from its host galaxy
  5. LIGO/VIRGO S190814bv: AbAO non-detection of AT2019nme
  6. LIGO/Virgo S190814bv: Prioritization of Counterpart Candidates based on a Photometric Redshift Analysis by the DECam-GROWTH Team
  7. LIGO/Virgo S190814bv: Not observable by CALET
  8. LIGO/Virgo S190814bv: Pan-STARRS imaging indicates DG19sevhc (AT2019npy) is a proper motion star
  9. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of desgw-190814e, DG19sevhc and selected galaxies
  10. LIGO/Virgo S190814bv: SOAR spectroscopy of 2 DESGW candidates
  11. LIGO/Virgo S190814bv: no candidates from optical imaging of selected galaxies at the NOT
  12. LIGO/Virgo S190814bv: No candidates from DCT galaxy targeted search and observations of DECam-GROWTH candidates
  13. LIGO/Virgo S190814bv: New candidates from DECam DESGW difference imaging search
  14. LIGO/Virgo S190814bv: GROND imaging of candidate galaxies
  15. S190814bv: MASTER analysis of DECam-GROWTH candidates
  16. LIGO/Virgo S190816i: Retraction of GW compact binary merger candidate
  17. LIGO/Virgo S190814bv: GRAWITA TNG infrared imaging of selected galaxies
  18. LIGO/Virgo S190814bv: des-gw190814b is a moving object
  19. LIGO/Virgo S190814bv: ATLAS forced photometry non-detections of DESGW candidates
  20. LIGO/Virgo S190814bv: KMTNet observation
  21. LIGO/Virgo S190814bv : No counterpart candidate in TAROT-GRANDMA observations
  22. LIGO/Virgo S190814bv: Candidates found in initial DESGW search
  23. LIGO/Virgo S190814bv: Upper limits from AGILE-GRID observations
  24. LIGO/Virgo S190814bv: Update on Sky-Localization and Source-Classification
  25. LIGO/Virgo S190814bv: no candidates from WHT imaging of candidate galaxies
  26. LIGO/Virgo S190814bv: GRAWITA TNG imaging of selected galaxies
  27. LIGO/Virgo S190814bv : no neutrino counterpart candidate in ANTARES search
  28. LIGO/Virgo S190814bv: Upper limits from Fermi-GBM Observations
  29. LIGO/Virgo S190814bv: Nordic Optical Telescope imaging of selected galaxies
  30. LIGO/Virgo S190814bv: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo S190814bv: Upper limits from IceCube neutrino searches
  32. LIGO/Virgo S190814bv: CLU/NED Galaxies in the 50% Localization Volume
  33. HAWC-190806A: Upper limits from Fermi-GBM Observations
  34. HAWC-190806A: Swift-XRT observations
  35. Trigger_11505: Tiled Swift observations
  36. LIGO/Virgo S190728q: New optical candidates from the DESGW program
  37. LIGO/Virgo S190808ae: Retraction of GW compact binary merger candidate
  38. LIGO/Virgo S190808ae: CLU/NED Galaxies in the 50% Localization Volume
  39. LIGO/Virgo S190808ae: No counterpart candidates in HAWC observations
  40. LIGO/Virgo S190808ae: One Coincident Neutrino Candidate from IceCube Search
  41. LIGO/Virgo S190808ae: Identification of a GW compact binary merger candidate
  42. HAWC Burst Alert 1008846_957: IceCube Neutrino Search
  43. GRB 190805B: Tiled Swift observations
  44. GRB 190804B: Tiled Swift observations
  45. IceCube 190730A: No counterpart candidates or blazar activity in GOTO observations
  46. GRB 190719C: VLT/X-shooter spectroscopic redshift of the host galaxy
  47. LIGO/Virgo S190727h: Updated sky localization
  48. GRB 190731A: Swift ToO observations
  49. IceCube-190730A: Upper limits from a search for additional neutrino events in IceCube
  50. IceCube-190730A - HAWC follow-up
  51. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
  52. IceCube 190730A: not observable by Fermi-GBM
  53. IceCube-190730A - IceCube observation of a high-energy neutrino candidate event
  54. LIGO/Virgo S190728q: Optical transients from Pan-STARRS coverage during first 2 nights
  55. LIGO/Virgo S190727h: Gaia Photometric Alerts transient candidate
  56. LIGO/Virgo S190728q/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
  57. LIGO/VIRGO S190728q: No candidate counterparts from ATLAS observations
  58. LIGO/Virgo S190728q: Third update on neutrino search with IceCube
  59. LIGO/Virgo S190728q: Update on Sky-Localization and Source-Classification
  60. LIGO/Virgo S190728q: ZTF19abjethn is inconsistent with new GW localization
  61. LIGO/Virgo S190728q: Identification of a Faint Blue Static Source at the Location of ZTF19abjethn
  62. LIGO/Virgo S190728q: Photometric Redshift and Stellar Mass Estimates for the Potential Host Galaxy of Optical Counterpart Candidate ZTF19abjethn
  63. LIGO/Virgo S190728q: Optical Candidate from the Zwicky Transient Facility ZTF19abjethn
  64. LIGO/Virgo S190728q: Second update on neutrino search with IceCube
  65. LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
  66. LIGO/Virgo S190728q: no counterpart candidates in AGILE-GRID observations
  67. LIGO/Virgo S190728q : no neutrino counterpart candidate in ANTARES search
  68. LIGO/Virgo S190728q: One neutrino candidate from IceCube search
  69. LIGO/Virgo S190728q: No counterpart candidates in HAWC observations
  70. LIGO/Virgo S190728q: Identification of a GW compact binary merger candidate
  71. LIGO/Virgo S190728q: Upper limits from IceCube neutrino searches
  72. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  73. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  74. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  75. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  76. LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
  77. LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
  78. LIGO/Virgo S190727h: Upper limits from IceCube neutrino searches
  79. LIGO/Virgo S190718y: Gaia Photometric Alerts transient candidates
  80. LIGO/Virgo S190720a: Updated localization from LIGO and Virgo data
  81. LIGO/Virgo S190720a: Upper limits from CALET observations
  82. GRB 190719C: Swift/UVOT Upper Limits
  83. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  84. LIGO/Virgo S190720a: Upper limits from AGILE-GRID observations
  85. LIGO/Virgo S190720a : no neutrino counterpart candidate in ANTARES search
  86. LIGO/Virgo S190720a: AGILE-MCAL observations
  87. LIGO/Virgo S190720a: Identification of a GW compact binary merger candidate
  88. LIGO/Virgo S190720a: No counterpart candidates in HAWC observations
  89. LIGO/Virgo S190720a: Upper limits from IceCube neutrino searches
  90. GRB 190719C: NOT candidate optical afterglow and host
  91. LIGO/Virgo S190718y: ZTF pre-detection of MASTER candidate AT2019lly
  92. LIGO/Virgo S190718y: Analysis update
  93. GRB 190719C: Swift detection of a burst
  94. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  95. LIGO/Virgo S190630ag: Updated sky localization
  96. LIGO/Virgo S190718y : no neutrino counterpart candidate in ANTARES search
  97. LIGO/Virgo S190718y: Identification of a GW compact binary merger candidate
  98. LIGO/Virgo S190718y: Upper limits from IceCube neutrino searches
  99. GRB 190718A: Swift detection of a burst
  100. IceCube-190712A: Upper limits from a search for additional neutrino events in IceCube

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