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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

3820 results found.

  1. Fermi GRB 241209A: Global MASTER-Net observations report
  2. Fermi Gamma-ray Burst Monitor trigger 755277791/241207641 is not a GRB
  3. Fermi GRB 241207A: Global MASTER-Net observations report
  4. GRB 241204A: DDOTI Upper Limits on the Afterglow
  5. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  6. EP241202b: Global MASTER-Net observations report
  7. GRB 241128A: AbAO optical upper limit
  8. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  9. GRB 241128A: Swift-BAT refined analysis
  10. GRB 241128A: Mondy optical observations
  11. Swift GRB 241128A: Global MASTER-Net observations report
  12. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  13. GRB 241129A: Fermi GBM Final Real-time Localization
  14. SVOM/GRM observation of GRB 241126B or a short burst from magnetar
  15. EP241126a: TRT optical counterpart detection
  16. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  17. SVOM/GRM detection of a short burst from SGR 1830
  18. GECAM detection of a short burst from SGR 1830
  19. Konus-Wind detection of GRB 241115D / EP 241115a
  20. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  21. Fermi GRB 241118A: Global MASTER-Net observations report
  22. EP241113b: Global MASTER-Net observations report
  23. SVOM/GRM detection of a short burst from SGR 1E1841-045
  24. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  25. Fermi trigger No 752990530: Global MASTER-Net observations report
  26. Fermi trigger No 752878030: Global MASTER-Net observations report
  27. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  28. EP241107a: FTW Optical and NIR observations of the optical counterpart
  29. GRB 241030A: Mondy optical observations
  30. Fermi GRB 241105A: Global MASTER-Net observations report
  31. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  32. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  33. EP241021a: OHP/T193 further optical observations
  34. LIGO/Virgo/KAGRA S241102br: Updated Sky localization
  35. EP241103a: Global MASTER-Net observations report
  36. GRB 241029A: GRBAlpha detection
  37. GRB241030A: OHP/T193 optical observations
  38. GRB 241029A: LCO optical detection
  39. Fermi trigger No 752006065: Global MASTER-Net observations report
  40. EP241021a: Swift-UVOT detection
  41. EP241021a: Optical rebrightening observations with Mephisto
  42. GRB 241029A: GROWTH-India Telescope optical follow up
  43. GRB 241029A: SAO RAS optical observations
  44. GRB 241026A: SAO RAS optical observations
  45. EP241021a: SAO RAS observations of rebrightening
  46. GRB 241029A: Fermi GBM Observation
  47. GRB 241029A: AKO Optical Afterglow Detection
  48. GRB 241029A: GOTO optical afterglow detection
  49. GRB 241029A: MASTER early optical counterpart detection
  50. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  51. GRB 241029A: Mephisto observations
  52. GRB 241029A: TRT optical afterglow candidate detection
  53. GRB 241029A: SVOM/GRM observation
  54. Fermi trigger No 751861204: Global MASTER-Net observations report
  55. GRB 241029A: Fermi GBM Final Real-time Localization
  56. Fermi GRB 241026A: Global MASTER-Net observations report
  57. EP241021a: optical follow-up observations with Xinglong Observatory
  58. Fermi trigger No 751554401: Global MASTER-Net observations report
  59. EP241025a (GRB 241025A): EP observations update
  60. GRB 241018A: Mondy optical upper limit
  61. Fermi trigger No 750788395: Global MASTER-Net observations report
  62. GRB 241013B: Fermi GBM Observation
  63. GRB 241013A: Fermi GBM Observation
  64. IceCube-241006A: Upper limits from a search for additional neutrino events in IceCube
  65. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  66. LIGO/Virgo/KAGRA S241007bw: Identification of a GW compact binary merger candidate
  67. LIGO/Virgo/KAGRA S241006k: Identification of a GW compact binary merger candidate
  68. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  69. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  70. Fermi GRB 241002B: Global MASTER-Net observations report
  71. GRB 241001A: Swift-XRT observations
  72. GRB 240929A: GRBAlpha detection
  73. Fermi-LAT Gamma-ray Observations of IceCube-240929A
  74. SVOM/GRM detection of a burst from SGR Swift J1818.0-1607
  75. IceCube-240929A: Upper limits from a search for additional neutrino events in IceCube
  76. LIGO/Virgo/KAGRA S240930df: 1 counterpart neutrino candidate event from an IceCube neutrino search
  77. GRB 240929A : Leavitt Observatory optical upper limit
  78. Fermi GRB 240930B: Global MASTER-Net observations report
  79. Fermi GRB 240930A: Global MASTER-Net observations report
  80. Fermi trigger No 749339671: Global MASTER-Net observations report
  81. Fermi Gamma-ray Burst Monitor trigger 749339671/240929913 is not a GRB
  82. GRB 240929A long GRB detected by INTEGRAL
  83. GRB 240929A: BALROG localization (Fermi Trigger 749332209 / GRB 240929826)
  84. Fermi GRB 240929A: Global MASTER-Net observations report
  85. GRB 240929A: Fermi GBM Final Real-time Localization
  86. Integral GRB240929.83: Global MASTER-Net observations report
  87. IceCube-240929A - IceCube observation of a high-energy neutrino candidate track-like event
  88. Insight-HXMT ToO observations of X-ray bursts from SGR 1E 1841-045 / Kes 73
  89. EP240913a/GRB 240913C: 1.6m Mephisto observations
  90. EP240918a: SVOM/VT upper limit
  91. LIGO/Virgo/KAGRA S240920dw: Identification of a GW compact binary merger candidate
  92. GRB 240821A: radio observation with the VLA
  93. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  94. EP240913a: JinShan optical upper limits
  95. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  96. Fermi trigger No 747553301: Global MASTER-Net observations report
  97. GRB 240905B: GOTO optical upper limits
  98. GRB 240905E: Swift detection of a burst
  99. Fermi GRB 240905B: Global MASTER-Net observations report
  100. LIGO/Virgo/KAGRA S240902bq: Identification of a GW compact binary merger candidate

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