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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"

32765 results found.

  1. EP240618a: GRANDMA Optical Upper Limits
  2. EP240618a: TRT optical upper limit
  3. Fermi GRB 240619A: Global MASTER-Net observations report
  4. EP240617a: STEP/T80S optical limits
  5. GRB 240615A: possible transient detection from Wendelstein observations
  6. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  7. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  8. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  9. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  10. GRB240615A: 1.3m DFOT optical upper limit
  11. EP240617a is likely a GRB event
  12. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  13. GRB 240615A: J-band upper limits from WINTER
  14. GRB 240615A: Fermi GBM Observation
  15. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  16. GRB 240615A: GECAM detection
  17. X-ray transient EP240414a: Chandra late time observation
  18. GRB 240615A: FLWO-1.2m optical upper limits
  19. Fermi GRB 240616A: Global MASTER-Net observations report
  20. Konus-Wind detection of GRB 240615A (short/hard)
  21. GRB 240615A: GOTO optical upper limits
  22. GRB 240615A: Swift ToO observations
  23. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  24. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  25. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  26. GRB 240603A: VZLUSAT-2 detection
  27. GRB 240612A: GRBAlpha detection
  28. Fermi GRB 240612B: Global MASTER-Net observations report
  29. Fermi GRB 240612A: Global MASTER-Net observations report
  30. GRB 240607A: GECAM detection of a bright long burst
  31. Fermi GRB 240611A: Global MASTER-Net observations report
  32. Konus-Wind detection of GRB 240607A
  33. EXO 0748-676: Swift-BAT refined analysis
  34. GRB 240529A: LBT optical detection and late temporal decay
  35. GRB 240529A : MITSuME Akeno optical afterglow detection
  36. Fermi GRB 240610A: Global MASTER-Net observations report
  37. IPN triangulation of GRB 240607A
  38. Fermi GRB 240608A: Global MASTER-Net observations report
  39. Konus-Wind detection of GRB 240606B
  40. Fermi GRB 240607A: Global MASTER-Net observations report
  41. GRB 240529A: NOEMA detection
  42. GRB 240607A: Fermi GBM Observation
  43. GRB 240606B: Fermi GBM Observation
  44. Swift Trigger 1235109: consistent with noise and not astrophysical
  45. GRB 240607A: AstroSat CZTI detection of bright long burst
  46. GRB 240607A: Fermi GBM detection of a very bright burst
  47. GRB 240529A: radio detection with AMI-LA
  48. GRB 240606B: GECAM-B detection a long burst
  49. GRB 240606B: Swift ToO observations
  50. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  51. Konus-Wind detection of GRB 240603A
  52. Fermi GRB 240604A: Global MASTER-Net observations report
  53. IPN triangulation of GRB 240531A (short)
  54. Fermi GRB 240605A: Global MASTER-Net observations report
  55. Fermi GRB 240605C: Global MASTER-Net observations report
  56. LIGO/Virgo/KAGRA S240601co: Updated Sky localization
  57. IPN triangulation of GRB 240603A
  58. GRB 240529A: SAO RAS optical observations
  59. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  60. Fermi GRB 240603C: Global MASTER-Net observations report
  61. Swift Trigger 1232465: consistent with noise
  62. GRB 240529A: MASTER prompt OT detection
  63. GRB 240529A: continued SAO RAS optical observations
  64. Fermi GRB 240602A: Global MASTER-Net observations report
  65. GRB 240529A: further SAO RAS optical observations
  66. LIGO/Virgo/KAGRA S240601aj: Updated Sky localization
  67. LIGO/Virgo/KAGRA S240601co: Identification of a GW compact binary merger candidate
  68. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  69. LIGO/Virgo/KAGRA S240530a: Updated Sky localization
  70. LXT 240528A: GSP optical upper limit
  71. GRB 240529A: 1.3m DFOT Optical observations
  72. LIGO/Virgo/KAGRA S240527en: Updated Sky localization
  73. LIGO/Virgo/KAGRA S240601aj: Identification of a GW compact binary merger candidate
  74. GRB 240529A : Mondy optical observations
  75. Konus-Wind detection of GRB 240529A
  76. IPN triangulation of the initial episode of GRB 240529A
  77. GRB 240529A: SAO RAS optical observations
  78. LIGO/Virgo/KAGRA S240531bp: Updated Sky localization
  79. LIGO/Virgo/KAGRA S240531bp: Identification of a GW compact binary merger candidate
  80. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  81. GRB 240529A: Insight-HXMT/HE detection
  82. GRB 240529A: optical photometry from Konkoly
  83. GRB 240529A: GROWTH-India optical follow-up
  84. GRB 240529A: T193/MISTRAL observations
  85. GRB 240529A: Redshift from GTC/OSIRIS+
  86. GRB 240529A: AKO Optical Afterglow Detection
  87. LIGO/Virgo/KAGRA S240530a: Identification of a GW compact binary merger candidate
  88. GRB 240529A: J-band detections with WINTER
  89. GRB 240529A: Skynet Optical Observations
  90. GRB 240529A: Swift-BAT refined analysis
  91. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  92. GRB 240529A: Swift/UVOT Detection
  93. GRB 240529A: NOT optical observations
  94. GRB 240529A: AstroSat CZTI detection
  95. GRB 240529A: GOTO optical afterglow detection
  96. LIGO/Virgo/KAGRA S240527fv: Updated Sky localization
  97. GRB 240527B: Fermi GBM Observation
  98. Fermi GRB 240527A: Global MASTER-Net observations report
  99. LIGO/Virgo/KAGRA S240527fv: Identification of a GW compact binary merger candidate
  100. GRB 240527B: Fermi-LAT detection

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