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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"

32687 results found.

  1. LIGO/Virgo/KAGRA S240621em: Updated Sky localization and Source Classification
  2. GRB 240529A: JinShan optical observations
  3. LIGO/Virgo/KAGRA S240621dy: Updated Sky localization and Source Classification
  4. LIGO/Virgo/KAGRA S240621eb: Updated Sky localization and Source Classification
  5. EP240618a: GSP optical upper limit
  6. LIGO/Virgo/KAGRA S240622h: Identification of a GW compact binary merger candidate
  7. LIGO/Virgo/KAGRA S240621em: Identification of a GW compact binary merger candidate
  8. LIGO/Virgo/KAGRA S240621eb: Identification of a GW compact binary merger candidate
  9. LIGO/Virgo/KAGRA S240621dy: Identification of a GW compact binary merger candidate
  10. IPN triangulation of GRB 240615A (short)
  11. X-ray transient EP240618a: Fermi/GBM non-detection
  12. GRB 240619A: GRBAlpha detection
  13. EP240618a: Swift/XRT upper limit
  14. EP240617a: tentative Swift/XRT detection of the afterglow
  15. GRB 240619A: Swift-XRT probable afterglow detection
  16. GRB 240619A: Swift ToO observations
  17. GRB 240619A: CALET Gamma-Ray Burst Monitor detection
  18. GRB 240619C: NuSTAR automated detection of the GRB
  19. GRB 240619A: Fermi GBM Observation
  20. Fermi GBM Sub-Threshold Detection of GRB 240619C
  21. GRB 240619A: GOTO candidate optical afterglow
  22. EP240618a: Abastumani optical observationsEP240618a
  23. GRB 240615A: NOT optical observations
  24. EP240618a: GRANDMA Optical Upper Limits
  25. EP240618a: TRT optical upper limit
  26. Fermi GRB 240619A: Global MASTER-Net observations report
  27. EP240617a: STEP/T80S optical limits
  28. GRB 240615A: possible transient detection from Wendelstein observations
  29. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  30. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  31. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  32. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  33. GRB240615A: 1.3m DFOT optical upper limit
  34. EP240617a is likely a GRB event
  35. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  36. GRB 240615A: J-band upper limits from WINTER
  37. GRB 240615A: Fermi GBM Observation
  38. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  39. GRB 240615A: GECAM detection
  40. X-ray transient EP240414a: Chandra late time observation
  41. GRB 240615A: FLWO-1.2m optical upper limits
  42. Fermi GRB 240616A: Global MASTER-Net observations report
  43. Konus-Wind detection of GRB 240615A (short/hard)
  44. GRB 240615A: GOTO optical upper limits
  45. GRB 240615A: Swift ToO observations
  46. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  47. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  48. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  49. GRB 240603A: VZLUSAT-2 detection
  50. GRB 240612A: GRBAlpha detection
  51. Fermi GRB 240612B: Global MASTER-Net observations report
  52. Fermi GRB 240612A: Global MASTER-Net observations report
  53. GRB 240607A: GECAM detection of a bright long burst
  54. Fermi GRB 240611A: Global MASTER-Net observations report
  55. Konus-Wind detection of GRB 240607A
  56. EXO 0748-676: Swift-BAT refined analysis
  57. GRB 240529A: LBT optical detection and late temporal decay
  58. GRB 240529A : MITSuME Akeno optical afterglow detection
  59. Fermi GRB 240610A: Global MASTER-Net observations report
  60. IPN triangulation of GRB 240607A
  61. Fermi GRB 240608A: Global MASTER-Net observations report
  62. Konus-Wind detection of GRB 240606B
  63. Fermi GRB 240607A: Global MASTER-Net observations report
  64. GRB 240529A: NOEMA detection
  65. GRB 240607A: Fermi GBM Observation
  66. GRB 240606B: Fermi GBM Observation
  67. Swift Trigger 1235109: consistent with noise and not astrophysical
  68. GRB 240607A: AstroSat CZTI detection of bright long burst
  69. GRB 240607A: Fermi GBM detection of a very bright burst
  70. GRB 240529A: radio detection with AMI-LA
  71. GRB 240606B: GECAM-B detection a long burst
  72. GRB 240606B: Swift ToO observations
  73. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  74. Konus-Wind detection of GRB 240603A
  75. Fermi GRB 240604A: Global MASTER-Net observations report
  76. IPN triangulation of GRB 240531A (short)
  77. Fermi GRB 240605A: Global MASTER-Net observations report
  78. Fermi GRB 240605C: Global MASTER-Net observations report
  79. LIGO/Virgo/KAGRA S240601co: Updated Sky localization
  80. IPN triangulation of GRB 240603A
  81. GRB 240529A: SAO RAS optical observations
  82. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  83. Fermi GRB 240603C: Global MASTER-Net observations report
  84. Swift Trigger 1232465: consistent with noise
  85. GRB 240529A: MASTER prompt OT detection
  86. GRB 240529A: continued SAO RAS optical observations
  87. Fermi GRB 240602A: Global MASTER-Net observations report
  88. GRB 240529A: further SAO RAS optical observations
  89. LIGO/Virgo/KAGRA S240601aj: Updated Sky localization
  90. LIGO/Virgo/KAGRA S240601co: Identification of a GW compact binary merger candidate
  91. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  92. LIGO/Virgo/KAGRA S240530a: Updated Sky localization
  93. LXT 240528A: GSP optical upper limit
  94. GRB 240529A: 1.3m DFOT Optical observations
  95. LIGO/Virgo/KAGRA S240527en: Updated Sky localization
  96. LIGO/Virgo/KAGRA S240601aj: Identification of a GW compact binary merger candidate
  97. GRB 240529A : Mondy optical observations
  98. Konus-Wind detection of GRB 240529A
  99. IPN triangulation of the initial episode of GRB 240529A
  100. GRB 240529A: SAO RAS optical observations

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