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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

45825 results found.

  1. GRB 241115A: LCOGT Optical Upper Limits
  2. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  3. Fermi GRB 241115B: Global MASTER-Net observations report
  4. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  5. EP241115a: Global MASTER-Net observations report
  6. GRB 241115B: Fermi GBM Final Real-time Localization
  7. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  8. EP241115a: EP detection of a fast X-ray transient
  9. EP241113a: No Detection in Fermi-GBM Observations
  10. Swift GRB 241115A: Global MASTER-Net observations report
  11. Fermi GRB 241115A: Global MASTER-Net observations report
  12. GRB 241115A: Swift detection of a burst
  13. GRB 241115A: Fermi GBM Final Real-time Localization
  14. EP 241113a: LBT possible optical counterpart
  15. GRB 241113B: KAIT Optical Afterglow Candidate
  16. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  17. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  18. GRB 241113A: Swift-BAT refined analysis
  19. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  20. GRB 241113A: PRIME near-infrared upper limits
  21. Fermi GRB 241114A: Global MASTER-Net observations report
  22. EP241113a: Global MASTER-Net observations report
  23. GRB 241114A: Fermi GBM Final Real-time Localization
  24. GRB 241113B: J-band upper limit from WINTER
  25. GRB 241113A: J-band observations with WINTER
  26. EP241113a : J-band observations with WINTER
  27. GRB 241030A: LCO optical observation
  28. GRB 241113B: Swift-XRT observations
  29. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  30. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  31. GRB 241113A: KAIT optical observations
  32. EP241113b: Global MASTER-Net observations report
  33. EP241113b/GRB 241113B: EP detection of GRB 241113B
  34. Fermi-LAT gamma-ray observations of IceCube-241113A
  35. GRB 241113B: SVOM/GRM observation
  36. EP241113a: EP on-board trigger and autonomous follow-up observation
  37. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  38. GRB 241113A: Swift-XRT refined Analysis
  39. EP241107a: SOAR upper limits
  40. GRB 241113A: Swift/UVOT Detection
  41. GRB 241113A: REM detection of the optical/NIR afterglow
  42. Konus-Wind detection of GRB 241107A (short/hard)
  43. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  44. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  45. GRB 241113B: Swift ToO observations
  46. GRB 241113A: LCO optical observations
  47. IceCube-241113A - IceCube observation of a high-energy neutrino candidate track-like event
  48. GRB 241112B: GMG Optical Upper Limit
  49. GRB 241113A: Enhanced Swift-XRT position
  50. GRB241113A: LCOGT (40-cm) optical counterpart detection
  51. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  52. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  53. GRB 241113A: Swift detection of a burst with an optical counterpart
  54. Swift GRB241113.33: Global MASTER-Net observations report
  55. SVOM/GRM detection of a short burst from SGR 1E1841-045
  56. Fermi trigger No 753166198: Global MASTER-Net observations report
  57. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  58. GRB 241105A: ATCA Radio Upper Limits
  59. GRB 241112B: AbAO optical upper limit
  60. GRB 241107A: GROWTH-India telescope optical upper limit
  61. IceCube Alert 241113.02: Global MASTER-Net observations report
  62. Fermi GRB 241112A: Global MASTER-Net observations report
  63. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  64. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  65. GRB 241112B: Swift-XRT afterglow detection
  66. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  67. GRB 241112B: SVOM/GRM observation
  68. GRB 241112B: SVOM/VT afterglow detection
  69. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  70. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  71. GRB 241112B: Mephisto optical upper limits
  72. GRB 241112B: GOTO optical upper limits
  73. GRB 241112B: Swift ToO observations
  74. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  75. GRB 241107A: INTEGRAL IBIS localization
  76. EP241107a: EP-FXT follow-up observations
  77. GRB 241112A: Fermi GBM Final Real-time Localization
  78. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  79. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  80. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  81. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  82. IPN triangulation of GRB 241107A (short/hard)
  83. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  84. GRB 241025C: VZLUSAT-2 detection
  85. GRB 241025A: VZLUSAT-2 detection
  86. GRB 241018A: cubesat Avion detection
  87. Fermi trigger No 752990530: Global MASTER-Net observations report
  88. GRB 241111A: Fermi GBM Final Real-time Localization
  89. GRB 241030B: TESS detection of optical counterpart
  90. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  91. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  92. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  94. Fermi trigger No 752878030: Global MASTER-Net observations report
  95. Integral GRB241109.89: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  97. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  98. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  99. INTEGRAL detection of a burst from 1E 1841-045
  100. EP241107a: AbAO optical upper limit

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