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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"

32795 results found.

  1. Fermi GRB 231030A: Global MASTER-Net observations report
  2. LIGO/Virgo/KAGRA S231029y: Identification of a GW compact binary merger candidate
  3. GRID detection of GRB 231020A
  4. GRB 231028A: AstroSat CZTI detection
  5. GRB 231028A: Glowbug gamma-ray detection
  6. GRB 231028A: Fermi GBM Detection
  7. Swift GRB 231028A: Global MASTER-Net observations report
  8. LIGO/Virgo/KAGRA S231028bg: Updated Sky localization
  9. LIGO/Virgo/KAGRA S231028bg: Identification of a GW compact binary merger candidate
  10. GRB 231028A: Swift detection of a burst
  11. GRB 231019A: Glowbug gamma-ray detection
  12. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  13. GRB 231025A: Fermi GBM Observation
  14. GRB 231024A: Fermi GBM Observation
  15. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  16. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  17. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  18. GRB 231020A: AstroSat CZTI detection
  19. GRB 231020B: AstroSat CZTI detection
  20. GRB 231024A: GOTO optical counterpart candidate
  21. The photometry of the transient in Messier 31 field: GMG observation
  22. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  23. LIGO/Virgo/KAGRA S231020bw: Updated Sky localization
  24. GRB 231020A: Fermi GBM Detection
  25. GRID detection of GRB 231004A
  26. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  27. GRB 231019A: VZLUSAT-2 detection
  28. GRB 231018A: VZLUSAT-2 detection
  29. LIGO/Virgo/KAGRA S231020ba: Updated Sky localization and EM Bright Classification
  30. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  31. GRB 231015A: NuSTAR Detection of Prompt Emission
  32. Fermi GRB 231020A: Global MASTER-Net observations report
  33. LIGO/Virgo/KAGRA S231020bw: Identification of a GW compact binary merger candidate
  34. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  35. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  36. GRB 231017A: 1.3m DFOT Optical upper limit
  37. LIGO/Virgo/KAGRA S231020ba: Identification of a GW compact binary merger candidate
  38. IceCube-231004A: Upper limits from Fermi-GBM Observations
  39. GRB 231018A: GRBAlpha detection
  40. GRB 231018A: CALET Gamma-Ray Burst Monitor detection
  41. Fermi GRB 231019A: Global MASTER-Net observations report
  42. GRB 231018A: Glowbug gamma-ray detection
  43. Konus-Wind detection of GRB 231018A
  44. IPN triangulation of GRB 231018A
  45. GRB 231017A: Swift/UVOT Upper Limit
  46. GRB 230911C: ATCA detection of possible radio counterpart
  47. GRB 231017A: GOTO optical upper limits
  48. GRB 231017A: JinShan optical upper limit
  49. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  50. IC231004A: Classification of AT2023uqf/ZTF23abidzvf as a rapidly-evolving supernova with CSM interaction
  51. GRB 231017A: Las Cumbres optical upper limit
  52. GRB 231015A: Glowbug gamma-ray detection
  53. GRB 231017A: LCOGT Optical Upper Limits
  54. GRB231017A: GROWTH-India upper limits on the optical afterglow
  55. GRB 231015A: AstroSat CZTI detection
  56. GRB 231018A: Fermi GBM Detection
  57. GRB 231017A: Fermi GBM Detection
  58. GRB 231017A: Swift-XRT observations
  59. GRB 231012B may not be a GRB
  60. GRB 231017A: Swift ToO observations
  61. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  62. Fermi-LAT gamma-ray observations of IceCube-231014A
  63. IceCube-231014A: Upper limits from a search for additional neutrino events in IceCube
  64. LIGO/Virgo/KAGRA S231014r: Identification of a GW compact binary merger candidate
  65. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  66. GRB 231004A: Glowbug gamma-ray detection
  67. LIGO/Virgo/KAGRA S231001aq: Updated Sky localization
  68. IceCube-231004A: One Candidate Counterpart from the Zwicky Transient Facility
  69. LIGO/Virgo/KAGRA S231008ap: Updated Sky localization
  70. LIGO/Virgo/KAGRA S231008ap: Identification of a GW compact binary merger candidate
  71. IceCube-231004A: Upper limits from a search for additional neutrino events in IceCube
  72. IceCube-231004A: No significant detection in HAWC
  73. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  74. Fermi-LAT gamma-ray observations of IceCube-231004A
  75. LIGO/Virgo/KAGRA S231005ah: Updated Sky localization
  76. LIGO/Virgo/KAGRA S231005ah: Identification of a GW compact binary merger candidate
  77. LIGO/Virgo/KAGRA S231005j: Updated Sky localization
  78. LIGO/Virgo/KAGRA S231005j: Identification of a GW compact binary merger candidate
  79. Update of IceCube-231004A - Corrected direciton
  80. transient AT2023sva: radio observations with AMI-LA
  81. GRB 230827B: 10.4m GTC spectroscopic redshift
  82. LIGO/Virgo/KAGRA S231001aq: Updated Sky localization
  83. LIGO/Virgo/KAGRA S230930al: Updated Sky localization
  84. LIGO/Virgo/KAGRA S230928cb: Updated Sky localization
  85. LIGO/Virgo/KAGRA S231001aq: Identification of a GW compact binary merger candidate
  86. LIGO/Virgo/KAGRA S230930al: Identification of a GW compact binary merger candidate
  87. NuEm-230927A: Swift-XRT follow-up
  88. LIGO/Virgo/KAGRA S230928cb: Identification of a GW compact binary merger candidate
  89. AT2023sva / GRB230916B: GIT observations of the afterglow
  90. transient AT2023sva: A Binary Driven Hypernova with a possible associated supernova
  91. LIGO/Virgo/KAGRA S230927be: Updated Sky localization
  92. LIGO/Virgo/KAGRA S230927l: Updated Sky localization
  93. LIGO/Virgo/KAGRA S230927be: Identification of a GW compact binary merger candidate
  94. LIGO/Virgo/KAGRA S230927l: Identification of a GW compact binary merger candidate
  95. Swift Triggers 1192740, 1192742 and 1192743 are not astrophysical events
  96. LIGO/Virgo/KAGRA S230922q: Updated Sky localization
  97. Konus-Wind detection of GRB 230919A
  98. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  99. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  100. LIGO/Virgo/KAGRA S230924an: Updated Sky localization

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