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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"

43139 results found.

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

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