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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').
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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"
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submitter:"Judith Racusin"

32693 results found.

  1. GRB 251214D: GECAM-B observation of a long burst
  2. GRB 251214B: Fermi GBM Observation
  3. GRB 251209A: Insight-HXMT/HE detection
  4. GRB 251215A: Swift ToO observations
  5. EP251214b (EP trigger 01709250023): LCO optical limits
  6. GRID detection of GRB 251213A
  7. GRB 251203B: AbAO optical observations
  8. GRB 251215A: Swift/BAT-GUANO arcminute localization of a burst
  9. GRB 251214B: GECAM-B observation of a long burst
  10. GRB 251213A: SVOM/GRM observation
  11. EP251214a: KAIT optical upper limit
  12. GRB 251213A: AstroSat CZTI detection
  13. GRB 251214A: AstroSat CZTI detection
  14. GRB 251214B: Swift/UVOT Detection
  15. GRB 251214B: COLIBRÍ observations of the afterglow
  16. EP251214a: EP-FXT non-detection and upper limit
  17. GRB 251214A: GECAM-B observation of a likely long burst
  18. GRB 251214B: 1.3m DFOT optical detection
  19. EP251214a: Global MASTER-Net observations report
  20. GRB 251214B: Xinglong-2.16m optical observation
  21. GRB 251214B : MASTER optical afterglow detection
  22. GRB 251214B: SVOM/C-GFT optical observations
  23. EP251214a: COLIBRÍ optical upper limit
  24. Swift GRB 251214B: Global MASTER-Net observations report
  25. EP251214a: EP-WXT detection of an X-ray transient possibly associated with GRB 251214A
  26. Fermi GRB 251214A: Global MASTER-Net observations report
  27. EP251212a: Global MASTER-Net observations report
  28. EP251212a: KAIT optical upper limit
  29. EP251212a / GRB 251212A: AstroSat CZTI detection
  30. EP251212a: EP-FXT follow-up observation
  31. GRB 251211B: AstroSat CZTI detection
  32. IceCube-251210A: No Candidate Transients from the Zwicky Transient Facility
  33. GRB 251209A: NuSTAR detection of prompt emission
  34. EP251212a : COLIBRÍ optical upper limit
  35. EP251212a: Einstein Probe detection of an X-ray transient
  36. Fermi-LAT Gamma-ray Observations of IceCube-251210A
  37. IceCube-251210A: Upper limits from a search for additional neutrino events in IceCube
  38. Fermi GRB 251211B: Global MASTER-Net observations report
  39. IceCube-251210A: DDOTI Optical Upper Limit
  40. GRB 251209A: Fermi GBM observation
  41. GRB 251205A: 1.3m DFOT optical upper limit
  42. GRB 251209A: AstroSat CZTI detection
  43. EP251124a: Mondy optical upper limit
  44. GRB 251129A/EP251129a: AbAO and Mondy optical observations
  45. EP251130a: Mondy and AbAO optical observations
  46. GRB 251208A: AstroSat CZTI detection
  47. Fermi GBM Sub-Threshold Detection of GRB 251205A
  48. GRB 251208A: Glowbug gamma-ray detection
  49. GRB 251208B: COLIBRÍ optical upper limits
  50. EP251118a / GRB 251118C: VLT/MUSE redshift confirmation
  51. GRB 251208C: GECAM-B observation of a short burst
  52. GRB 251208A: GECAM-B observation of a short burst
  53. Fermi GRB 251209A: Global MASTER-Net observations report
  54. Fermi GRB 251208C: Global MASTER-Net observations report
  55. GRB 251206A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  56. GRB 251208B: Swift-XRT afterglow detection
  57. GRB 251208D: LAST optical upper limit
  58. GRB 251208D: LCO analysis of the XRT sources
  59. GRB 251208B: Fermi GBM Observation
  60. GRB 251208B: GROWTH-India Telescope optical upper limits
  61. GRB 251205A: J-band detection with WINTER
  62. GRB 251208D: Swift-XRT observations
  63. GRB 251208A: SVOM/GRM observation of a short burst
  64. GRB 251208C: SVOM/GRM observation of a short burst
  65. GRB 251129A: e-MERLIN C-band observations
  66. GRB 251205A: Liverpool Telescope further optical follow-up observations
  67. GRB 251208D: LCO optical upper limits
  68. GRB 251208B: Swift ToO observations
  69. GRB 251208B: Fermi-LAT detection
  70. GRB 251208B: Swift/BAT-GUANO arcminute localization of a burst
  71. GRB 251208D: SVOM possible detection of a faint burst
  72. GRB 251205A : MITSuME Akeno optical afterglow candidate detection
  73. GRB 251205A: FTW optical and NIR observations
  74. EP-WXT trigger 01709249380: KAIT confirmation of a stellar flare
  75. GRB 251205A: Liverpool Telescope further optical follow-up observations
  76. EP-WXT trigger 01709249380: confirmation of a stellar flare by BOOTES-5
  77. GRB 251205A: ZTF and ATLAS optical afterglow detections
  78. GRB 251205A: GROWTH-India Telescope optical observations
  79. GRB 251205A: Swift-BAT refined analysis
  80. GRB 251205A: Swift/UVOT Detection
  81. GRB 251205A: Liverpool Telescope optical follow-up observations
  82. GRB 251203C: Swift/UVOT Upper Limit
  83. Konus-Wind detection of GRB 251118A
  84. GRB 251205A: Zeiss-1000 Koshka observatory optical observations
  85. GRB 251205A: COLIBRÍ optical observations
  86. GRB 251205A: GOTO optical afterglow detection
  87. GRB 251205A: NOT optical observations
  88. GRB 251205A: GTC/OSIRIS+ redshift z = 1.100
  89. Swift GRB 251205A : MASTER OT detection with host galaxy
  90. GRB 251203A: Insight-HXMT/HE detection
  91. GRB 251203C: SVOM/ECLAIRs refined analysis
  92. GRB 251202A / EP251202a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm and 1-m telescopes at McDonald Observatory
  93. GRB 251203C: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  94. GRB 251202A: SVOM/GRM observation
  95. GRB 251203A: GECAM-B observation of a burst
  96. GRB 251203A: SVOM/GRM observation
  97. GRB 251201B: SALT spectroscopic redshift z = 1.599
  98. GRB 251203C: J-band observations with WINTER
  99. GRB 251129B: Glowbug gamma-ray detection of a short burst
  100. GRB 251203A: AstroSat CZTI detection

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