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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.

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

37746 results found.

  1. GRB 231215A: Redshift from OSIRIS+ / GTC
  2. GRB 231205B: VZLUSAT-2 detection
  3. GRB 231204A: VZLUSAT-2 detection
  4. GRB 231215A: GAD Observatory, La Spezia, Italy upper limit;
  5. GRB 231215A: Fermi GBM observation
  6. GRB 231215A: CALET Gamma-Ray Burst Monitor detection
  7. GRB 231215A : OHP/T193 optical afterglow detection
  8. GRB 231215A: Swift/UVOT Detection
  9. GRB 231215A: Swift-XRT refined Analysis
  10. GRB 231215A: BOOTES-4/MET optical detection
  11. GRB 231215A: AKO Optical Upper Limit
  12. GRB 231215A: AGILE detection
  13. GRB 231214A: Fermi GBM observation
  14. Konus-Wind detection of GRB 231210B
  15. ATCA observations of GRB 231210B
  16. GRB 231215A: Enhanced Swift-XRT position
  17. Fermi trigger No 724326442: Global MASTER-Net observations report
  18. GRB 231214A: REM optical/NIR upper limits
  19. GRB 231215A: GROWTH-India optical follow-up
  20. GRB 231215A : Nanshan/HMT optical observations
  21. GRB 231215A: AstroSat CZTI detection
  22. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  23. GRB 231214A: Swift-XRT refined Analysis
  24. GRB 231215A: Mondy optical bright afterglow detection
  25. GRB 231214A: AstroSat CZTI detection
  26. GRB 231215C: MASTER OT detection
  27. GRB 231215A: Swift-XRT observations
  28. GRB 231215B: Fermi GBM Final Real-time Localization
  29. GRB 231215A: Swift detection of a burst
  30. GRB 231214A: Fermi-LAT detection
  31. GRB 231214A: Enhanced Swift-XRT position
  32. GRB 231214B: Swift/BAT-GUANO detection of a burst
  33. GRB231214A: BOOTES-6/DPRT optical upper limit
  34. Fermi trigger No 724278269: Global MASTER-Net observations report
  35. Fermi trigger No 724233240: Global MASTER-Net observations report
  36. GRB 231214A: Swift detection of a burst
  37. GRB 231214A: Fermi GBM Final Real-time Localization
  38. GRB 231210B: REM optical/NIR upper limits
  39. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 2047+098, located inside the IceCube-231211A error region
  40. IceCube-231211A - IceCube observation of a high-energy neutrino candidate track-like event
  41. LIGO/Virgo/KAGRA S231206cc: Upper limits from Swift/BAT-GUANO
  42. LIGO/Virgo/KAGRA S231206ca: Upper limits from Swift/BAT-GUANO
  43. GRB 231212A: GECAM-C detection of a likely short burst
  44. Fermi trigger No 724035412: Global MASTER-Net observations report
  45. GRB 231210B: MeerLICHT afterglow observations
  46. GRB 231210B: Swift-BAT refined analysis
  47. GRB 231210B: Swift-XRT refined Analysis
  48. GRB 231210B: Enhanced Swift-XRT position
  49. GRB 231210B: VLT/X-shooter redshift
  50. GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
  51. Fermi trigger No 723906955: Global MASTER-Net observations report
  52. GRB 231210B: Swift detection of a burst with optical counterpart
  53. IPN triangulation of GRB 231129C
  54. GRB 231210A: Fermi GBM Final Real-time Localization
  55. GRB 231208A: GRBAlpha detection
  56. GRB231205B: Swift/UVOT Upper Limits
  57. GRB 231208A: Glowbug gamma-ray detection
  58. GRB 231208A: AstroSat CZTI detection of a faint burst
  59. IPN triangulation of GRB 231205A
  60. GRB 231205B: Swift-BAT refined analysis
  61. GRB 231205B: 1.3m DFOT Optical upper limit
  62. GRB 231206A: joint location of multiple instruments by ETJASMIN
  63. GRB 231205B: optical upper limit in TSHAOand AbAO
  64. GRB231115A: TURBO Pre-Burst Optical Upper Limits
  65. GRB 231205B: AGILE detection
  66. Fermi trigger No 723581802: Global MASTER-Net observations report
  67. GRB 231206B: Fermi GBM Final Real-time Localization
  68. GRB 231205B: Ondrejov D50 optical upper limit
  69. GRB 231205B: Swift-XRT refined Analysis
  70. Fermi-LAT gamma-ray observations of IceCube-231202A
  71. GRB 231205B: REM optical/NIR upper limits
  72. GRB 231129C: ASIM MXGS observation and localization
  73. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  74. GRB 231205B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  75. GRB 231206A: GECAM-B detection of a short burst (correction)
  76. GRB 231205B : MITSuME Akeno optical upper limits
  77. GRB 231206A: GECAM-B detection of a short burst
  78. GRB 231205B: Zadko observatory - Gingin optical observations
  79. GRB 231205B: Gaoyazi/GOT optical upper limit
  80. GRB 231205B: Nanshan/HMT optical upper limit
  81. GRB 231205B: GECAM-B detection of a long burst
  82. GRB 231205B: LCOGT Optical Upper Limits
  83. GRB 231205A: DDOTI Upper Limits on the Afterglow
  84. GRB 231205B: Enhanced Swift-XRT position
  85. GRB 231204A: Glowbug gamma-ray detection
  86. GRB 231204A: CALET Gamma-Ray Burst Monitor detection
  87. Fermi-LAT daily aperture light curve of T CrB now available
  88. GRB 231205B: AKO Optical Upper Limit
  89. GRB 231205B: Swift detection of a burst
  90. GRB 231205A: joint location of multiple instruments by ETJASMIN
  91. GRB 231204A: AstroSat CZTI detection
  92. GRB 231205A: GECAM-B detection of a short burst
  93. Fermi trigger No 723435916: Global MASTER-Net observations report
  94. Fermi trigger No 723326169: Global MASTER-Net observations report
  95. GRB 231205A: Fermi GBM Final Real-time Localization
  96. LIGO/Virgo/KAGRA S231129ac: Upper limits from Swift/BAT-GUANO
  97. Fermi trigger No 723412808: Global MASTER-Net observations report
  98. GRB 231203A: Fermi GBM Observation
  99. GRB 231204A: Fermi GBM Final Real-time Localization
  100. GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV

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