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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
  1. IceCube-230708A - Correction to GCN Circular 34170
  2. Fermi trigger No 710741042: Global MASTER-Net observations report
  3. GRB 230709C: GRBAlpha detection
  4. GRB 230709B: GRBAlpha detection
  5. GRB 230709C: Fermi GBM Detection
  6. GRB 230709C: Fermi GBM Final Localization
  7. GRB 230707B: Fermi GBM Observation
  8. GRB 230710A: Fermi GBM Final Real-time Localization
  9. LIGO/Virgo/KAGRA S230708z: Identification of a GW compact binary merger candidate
  10. LIGO/Virgo/KAGRA S230708t: Identification of a GW compact binary merger candidate
  11. IceCube-230707A: No candidates detected by Swift-XRT
  12. Swift Trigger 1178410 is not an astrophysical event
  13. GRB 230709C: AstroSat CZTI detection
  14. LIGO/Virgo/KAGRA S230708cf: Updated Sky localization
  15. GRB 230707B: CALET Gamma-Ray Burst Monitor detection
  16. GRB 230703A detected with multiple GRID detectors
  17. GRB 230709C: BALROG localization (Fermi Trigger 710617111 / GRB 230709735)
  18. LIGO/Virgo/KAGRA S230707ai: Updated Sky localization
  19. IceCube-230707A: No candidates from the Zwicky Transient Facility
  20. Fermi-LAT gamma-ray observations of IceCube-230708A
  21. Fermi-LAT gamma-ray observations of IceCube-230707B
  22. Fermi-LAT gamma-ray observations of IceCube-230707A
  23. LIGO/Virgo/KAGRA S230630am: Updated Sky localization
  24. LIGO/Virgo/KAGRA S230630am: Updated Sky localization
  25. GRB 230709B: BALROG localization (Fermi Trigger 710614579 / GRB 230709706)
  26. IceCube-230708A: Upper limits from a search for additional neutrino events in IceCube
  27. IceCube-230707B: Upper limits from a search for additional neutrino events in IceCube
  28. IceCube-230707A: Upper limits from a search for additional neutrino events in IceCube
  29. LIGO/Virgo/KAGRA S230709bi: Identification of a GW compact binary merger candidate
  30. Swift Trigger 1178410: possible GRB 230709A
  31. LIGO/Virgo/KAGRA S230708cf: Identification of a GW compact binary merger candidate
  32. LIGO/Virgo/KAGRA S230708bi: Retraction of GW compact binary merger candidate
  33. GRB 230628C: GRID Detection
  34. IceCube-230708A - IceCube observation of a high-energy neutrino candidate track-like event
  35. GRB 230707B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  36. GRB 230707A: Swift-XRT observations
  37. IceCube Alert 230708.35: Global MASTER-Net observations report
  38. IceCube-230707B - IceCube observation of a high-energy neutrino candidate track-like event
  39. GRB 230707B: Fermi GBM Final Real-time Localization
  40. IceCube Alert 230707.71: Global MASTER-Net observations report
  41. IceCube-230707A - IceCube observation of a high-energy neutrino candidate track-like event
  42. GRB 230707A: Fermi GBM Detection
  43. LIGO/Virgo/KAGRA S230707ai: Identification of a GW compact binary merger candidate
  44. GRB 230707A: Swift ToO observations
  45. GRB 230707A: Swift/BAT-GUANO arcminute localization of a burst
  46. ZTF23aaoohpy/AT2023lcr : HCT follow-up observations
  47. Fermi GRB 230707A: Global MASTER-Net observations report
  48. GRB 230707A: Fermi GBM Final Real-time Localization
  49. LIGO/Virgo/KAGRA S230706ah: Updated Sky localization
  50. Integral GRB230706.70: Global MASTER-Net observations report
  51. LIGO/Virgo/KAGRA S230704f: Updated Sky localization
  52. LIGO/Virgo/KAGRA S230630bq: Updated Sky localization
  53. IBAS trigger number 10311: not a real GRB
  54. LIGO/Virgo/KAGRA S230702an: Updated Sky localization
  55. GRB 230625A: Detection by GRID
  56. LIGO/Virgo/KAGRA S230529ay: Updated Sky localization and EM Bright Classification
  57. LIGO/Virgo/KAGRA S230706ah: Identification of a GW compact binary merger candidate
  58. LIGO/Virgo/KAGRA S230627c: GECKO optical follow-up observations of host galaxy candidates and ZTF23aaptsuy/AT2023lxu
  59. ZTF23aaoohpy/AT2023lcr: AMI-LA radio detection
  60. Fermi trigger No 710117592: Global MASTER-Net observations report
  61. GRB 230626A: VZLUSAT-2 detection
  62. LVK S230619bd/GBM-230619: Upper limits from a two-week IceCube neutrino search
  63. GRB 230328B: LBT detection of the likely host galaxy
  64. LIGO/Virgo/KAGRA S230704f: Identification of a GW compact binary merger candidate
  65. Konus-Wind detection of GRB 220623A
  66. GRB 230701B: AstroSat CZTI detection
  67. LIGO/Virgo/KAGRA S230627c: observations of ZTF23aaptsuy/AT2023lx in AbAO observatory
  68. LIGO/Virgo/KAGRA S230702an: Identification of a GW compact binary merger candidate
  69. GRB 230628E: Swift/UVOT Detection
  70. GRB 230628E: Swift-BAT refined analysis
  71. GRB 230702A: Fermi GBM Final Real-time Localization
  72. GRB 230628E: ATCA rapid radio follow-up
  73. GRB 230701A: Fermi GBM Final Real-time Localization
  74. LIGO/Virgo/KAGRA S230627c: GRANDMA observations of galaxies and ZTF counterpart candidates
  75. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230701z: one counterpart neutrino candidate from IceCube neutrino searches
  76. LIGO/Virgo/KAGRA S230627c: Upper limits from Swift/BAT-GUANO
  77. LIGO/Virgo/KAGRA S230630bq: Identification of a GW compact binary merger candidate
  78. IPN triangulation of GRB 230625B (ultra-long)
  79. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): ALMA 100 GHz Detection
  80. LIGO/Virgo/KAGRA S230630am: Identification of a GW compact binary merger candidate
  81. GRB 230625B: CALET Gamma-Ray Burst Monitor detection
  82. GRB 230628E - VLT spectroscopic observations
  83. ZTF23aaoohpy/AT2023lcr: LBT observations
  84. Fermi GRB 230628C: Global MASTER-Net observations report
  85. GRB 230625B: AstroSat CZTI detection
  86. GRB230628E: VLT optical identification of afterglow candidate
  87. GRB 230628E: Swift-XRT refined Analysis
  88. GRB 230628E: Enhanced Swift-XRT position (Correction to name in GCN 34115)
  89. GRB 230628A: Enhanced Swift-XRT position
  90. Fermi GRB 230628D: Global MASTER-Net observations report
  91. LIGO/Virgo/KAGRA S230628ax: Identification of a GW compact binary merger candidate
  92. GRB 230628E: LCOGT Optical Upper Limit
  93. Swift GRB230628.93: Global MASTER-Net observations report
  94. GRB 230628E: Swift detection of a burst
  95. GRB 230628D: BALROG localization (Fermi Trigger 709676556 / GRB 230628849)
  96. GRB 230628D: Fermi GBM Final Real-time Localization
  97. LIGO/Virgo/KAGRA low-significance gravitational wave candidate S230628aj: one counterpart neutrino candidate from IceCube neutrino searches
  98. GRB 230628C: Fermi GBM Final Real-time Localization
  99. GRB 230628B: Swift/BAT-GUANO detection of a burst outside the coded FOV
  100. GRB 230623B: CALET Gamma-Ray Burst Monitor detection

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