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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"

32794 results found.

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

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