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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"

43901 results found.

  1. GRB 261026A: SVOM/ECLAIRs refined analysis
  2. GRB 261024C: GECAM-B observation
  3. GRB 261026B: AstroSat CZTI detection
  4. GRB 261024D: Insight-HXMT/HE detection
  5. GRB261026A: Infrared detection with MDM/MIRAGE
  6. GRB 261026A: SVOM/VT optical blue bump
  7. GRB 261026A: SAO RAS optical observations
  8. GRB 261024D: GECAM-B observation
  9. The EP-WXT trigger 01709321750 is likely a flaring star
  10. EP Alert 261026.29: Global MASTER-Net observations report
  11. GRB 261026A: EP-FXT follow-up observation
  12. GRB 261024A: SVOM/GRM observation
  13. GRB 261026A: Upper Limit with 60cm Panzhihua Telescope
  14. EP 261025a: J-band upper limit with MIRAGE
  15. GRB 261026A: OHP/T120 optical imaging
  16. GRB 261024D: Glowbug gamma-ray detection
  17. GRB 261026B: NuSTAR detection of prompt emission
  18. GRB 261024D: NuSTAR detection of prompt emission
  19. GRB 261024C: NuSTAR detection of prompt emission
  20. GRB 261026A: Ondrejov D50 optical limit
  21. GRB 261026A: ULL-ASTRO-MASTER optical detection with LCO 40-cm telescope at Haleakalā Observatory
  22. GRB 261026A: J-band observations by the SYSU 80cm infrared telescope
  23. GRB 261026A: SVOM/VT optical observations
  24. IPN triangulation of GRB 260730B
  25. GRB 261026C: Fermi GBM Final Real-time Localization
  26. GRB 261020A: Insight-HXMT/HE detection
  27. SVOM GRB261026.26: Global MASTER-Net observations report
  28. GRB 261026A: WINTER J-band observations
  29. GRB 261024D: AstroSat CZTI detection of a long burst
  30. GRB 261024C: AstroSat CZTI detection of a long burst
  31. GRB 261019A: GECAM-B observation
  32. GRB 261019A: SVOM/GRM observation
  33. Fermi GRB 261026B: Global MASTER-Net observations report
  34. GRB 261026A: SVOM/VT optical observation from VHF data
  35. GRB 261026A: KAIT optical observations
  36. GRB 261026A: SVOM/COLIBRÍ (FM-GFT) optical observations
  37. GRB 261026B: Fermi GBM Final Real-time Localization
  38. GRB 261024A: NuSTAR detection of prompt emission
  39. GRB 261026A: SVOM detection of a burst
  40. GRB 261025B: Fermi GBM Final Real-time Localization
  41. EP261025a: J-band upper limit with WINTER
  42. EP261023a: J-band upper limit with WINTER
  43. EP 261025a: COLIBRÍ optical upper limit
  44. EP261025a: Einstein Probe detection of a fast X-ray transient
  45. GRB 261025A: Fermi GBM Final Localization Correction
  46. EP261023a: J band upper limit by SYSU 80cm infrared telescope
  47. GRB 261024B: Fermi GBM Final Real-time Localization
  48. EP261015a: VST optical observations
  49. GRB 261024A: BALROG localization (Fermi Trigger 814551785 / GRB 261024683)
  50. GRB 261024A: Fermi GBM Final Real-time Localization
  51. EP261023a: Mondy optical upper limit
  52. EP261015a: MAO/AZT-22 optical observations
  53. EP261015a: VLA non-detection
  54. EP261023a: NOT optical counterpart candidate
  55. EP261023a: Einstein Probe detection of an X-ray transient
  56. GRB 261019A: Insight-HXMT/HE detection
  57. The EP-WXT trigger 01709321472 is likely a flaring star
  58. IceCube-261020A: Upper limits from a search for additional neutrino events in IceCube
  59. NuSTAR 261020, a 830s hard X-ray transient
  60. EP261015a: GSP multiband optical follow-up observations
  61. GRB 261017A: SVOM/GRM observation
  62. GRB 261021A: Fermi GBM Final Real-time Localization
  63. EP261015a: Further optical observations with the 1.3m DFOT
  64. GRB 261020B: AstroSat CZTI detection of a short burst
  65. Fermi-LAT Gamma-ray Observations of IceCube-261020A
  66. EP261015a: AZT-20 Assy-Turgen optical observations
  67. GRB 261020A: Fermi GBM Observation
  68. GRB 261017A: SAO RAS optical upper limit
  69. EP261015a: Wendelstein 43 cm optical observations
  70. GRB 260903A
  71. EP261015a: Follow-up with the 1.3m DFOT
  72. EP261015a: Terskol Zeiss-2000 optical upper limit
  73. EP261007b: Further EP-FXT follow-up observations
  74. GRB 261017A: COLIBRÍ optical upper limit
  75. IceCube-261020A - IceCube observation of a high-energy neutrino candidate track-like event
  76. GRB 261020A: MAXI GSC detection
  77. GRB 261020A: Fermi GBM Final Real-time Localization
  78. EP261015a: COLIBRÍ optical observations of a rebrightening
  79. Konus-Wind detection of GRB 261017A
  80. GRB 261019A: Fermi GBM Final Localization
  81. GRB 261017A: Possible Swift/UVOT Detection
  82. GRB 261017A: Luminance-band upper limit from a 28cm telescope in Chengde
  83. GRB 261017A: Swift-BAT refined analysis
  84. GRB 261017A: a short minimum variability timescale compatible with a compact object merger origin
  85. EP261015b: NOT Optical Observations
  86. GRB 261017A: J band upper limit by the SYSU 80cm infrared telescope
  87. EP261015c: refined analysis of the EP-FXT observation favors a stellar flare interpretation
  88. GRB 261017A : MITSuME Akeno optical upper limits
  89. GRB 261017A: Swift-XRT refined Analysis
  90. GRB 261017A: Nanshan/NEXT optical upper limit
  91. GRB 261017A: Enhanced Swift-XRT position
  92. GRB 261017A: Fermi GBM Observation
  93. GRB261010A: Retraction of Keck/MOSFIRE near-IR source
  94. GRB 261017A: Swift detection of a burst
  95. GRB 261017A: Fermi GBM Final Real-time Localization
  96. EP261015a: Tentative fading of the candidate optical counterpart from the NOT
  97. EP261015b: Refined analysis of EP-FXT observations
  98. EP261015b: J-band upper limit by the SYSU 80cm infrared telescope
  99. EP261015a: refined analysis of EP-FXT observations
  100. EP261015c: J-band upper limit with WINTER

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