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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"

43136 results found.

  1. GRB 241030A: LCO optical observation
  2. GRB 241113B: Swift-XRT observations
  3. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  4. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  5. GRB 241113A: KAIT optical observations
  6. EP241113b: Global MASTER-Net observations report
  7. EP241113b/GRB 241113B: EP detection of GRB 241113B
  8. Fermi-LAT gamma-ray observations of IceCube-241113A
  9. GRB 241113B: SVOM/GRM observation
  10. EP241113a: EP on-board trigger and autonomous follow-up observation
  11. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  12. GRB 241113A: Swift-XRT refined Analysis
  13. EP241107a: SOAR upper limits
  14. GRB 241113A: Swift/UVOT Detection
  15. GRB 241113A: REM detection of the optical/NIR afterglow
  16. Konus-Wind detection of GRB 241107A (short/hard)
  17. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  18. GRB 241113B: Swift ToO observations
  19. GRB 241113A: LCO optical observations
  20. IceCube-241113A - IceCube observation of a high-energy neutrino candidate track-like event
  21. GRB 241112B: GMG Optical Upper Limit
  22. GRB 241113A: Enhanced Swift-XRT position
  23. GRB241113A: LCOGT (40-cm) optical counterpart detection
  24. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  25. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  26. GRB 241113A: Swift detection of a burst with an optical counterpart
  27. Swift GRB241113.33: Global MASTER-Net observations report
  28. SVOM/GRM detection of a short burst from SGR 1E1841-045
  29. Fermi trigger No 753166198: Global MASTER-Net observations report
  30. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  31. GRB 241105A: ATCA Radio Upper Limits
  32. GRB 241107A: GROWTH-India telescope optical upper limit
  33. IceCube Alert 241113.02: Global MASTER-Net observations report
  34. Fermi GRB 241112A: Global MASTER-Net observations report
  35. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  36. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  37. GRB 241112B: Swift-XRT afterglow detection
  38. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  39. GRB 241112B: SVOM/GRM observation
  40. GRB 241112B: SVOM/VT afterglow detection
  41. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  42. GRB 241112B: Mephisto optical upper limits
  43. GRB 241112B: GOTO optical upper limits
  44. GRB 241112B: Swift ToO observations
  45. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  46. GRB 241107A: INTEGRAL IBIS localization
  47. EP241107a: EP-FXT follow-up observations
  48. GRB 241112A: Fermi GBM Final Real-time Localization
  49. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  50. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  51. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  52. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  53. IPN triangulation of GRB 241107A (short/hard)
  54. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  55. GRB 241025C: VZLUSAT-2 detection
  56. GRB 241025A: VZLUSAT-2 detection
  57. GRB 241018A: cubesat Avion detection
  58. Fermi trigger No 752990530: Global MASTER-Net observations report
  59. GRB 241111A: Fermi GBM Final Real-time Localization
  60. GRB 241030B: TESS detection of optical counterpart
  61. LIGO/Virgo/KAGRA S241110br: Updated Sky localization
  62. LIGO/Virgo/KAGRA S241110bk: 1 counterpart neutrino candidate event from an IceCube neutrino search
  63. LIGO/Virgo/KAGRA S241110br: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  65. Fermi trigger No 752878030: Global MASTER-Net observations report
  66. Integral GRB241109.89: Global MASTER-Net observations report
  67. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  68. EP241109a: KAIT photometry and 3 m Shane spectroscopy from Lick observatory
  69. LIGO/Virgo/KAGRA S241109bn: Updated Sky localization and EM Bright Classification
  70. INTEGRAL detection of a burst from 1E 1841-045
  71. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  72. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  73. LIGO/Virgo/KAGRA S241109p: Updated Sky localization and Source Classification
  74. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  75. LIGO/Virgo/KAGRA S241109bn: Identification of a GW compact binary merger candidate
  76. EP241109a: confirmation of a stellar flare by BOOTES-7
  77. EP241109a: EP on-board trigger and autonomous follow-up observation
  78. GRB 241108A: Swift-XRT observations
  79. LIGO/Virgo/KAGRA S241109p: Identification of a GW compact binary merger candidate
  80. EP241107A: MASTER optical observations of xray transient
  81. EP241107a: KAIT optical observations
  82. GRB 241108A: Swift ToO observations
  83. GRB 241030A: TESS observations
  84. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  85. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  86. EP241107a: Kinder optical follow-up observations
  87. GRB 241025A: radio detection with the VLA
  88. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  89. EP241107a: AKO Optical Afterglow Follow-Up Observations
  90. EP241107a: GSP detects optical counterpart
  91. EP241107a: Gemini-South spectroscopic confirmation (z = 0.456)
  92. GRB 241107A: SVOM/GRM detection of a short burst
  93. GRB 241105A: EP-FXT follow-up observations
  94. GRB 241105A: SVOM/GRM observation
  95. EP241107a: OHP/T193 photometric and spectroscopic observations
  96. GRB 241105a: PRIME near-infrared upper limits
  97. EP241107a: FTW Optical and NIR observations of the optical counterpart
  98. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  99. EP241107a: GIT optical observations
  100. EP241107a: Global MASTER-Net observations report

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