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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"

45798 results found.

  1. GRB 240414A: Fermi GBM Observation
  2. Fermi GRB 240415A: Global MASTER-Net observations report
  3. GRB 240415A: Mondy optical transient detection
  4. GRB 240414A: Photometric observation from 2.2m CAHA
  5. IceCube-240412A: Upper limits from a search for additional neutrino events in IceCube
  6. GRB 240414A: Swift/UVOT Detection
  7. LXT 240402A/GRB 240402B: Swift follow-up observations
  8. GRB 240414A: Mondy optical observations
  9. GRB 240414B: Fermi GBM Final Real-time Localization
  10. GRB 240414A: AKO Optical Upper Limit
  11. X-ray transient EP 240414a - GTC spectroscopic observations
  12. GRB 240415A: Prompt Swift-XRT observations
  13. GRB 240415A: Swift detection of a burst
  14. GRB 240415A: Fermi GBM Final Real-time Localization
  15. EP240413a: Upper limits from GECAM-B Observation
  16. EP 240414a: NOT optical counterpart confirmation
  17. GRB 240414A: Swift-XRT refined Analysis
  18. GRB240414A : J-band upper limits from WINTER
  19. GRB 240414A: Enhanced Swift-XRT position
  20. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  21. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  22. LIGO/Virgo/KAGRA S240413p: No Counterparts in DDOTI/OAN Optical Observations
  23. EP240413A: GOTO optical upper limits
  24. GRB 240414A: Skynet Optical Afterglow Observations
  25. Fermi trigger No 734754044: Global MASTER-Net observations report
  26. Swift GRB 240414A: Global MASTER-Net observations report
  27. EP240414a: Kinder optical counterpart candidate possibly associated with the galaxy SDSS J124601.99-094309.3
  28. IPN triangulation of GRB 240410A
  29. EP240413a: possible detection of the X-ray emission with EP-FXT after 14 hours
  30. EP240414a: EP-WXT detection of a fast X-ray transient
  31. IPN triangulation of GRB 240411A
  32. Fermi-LAT gamma-ray observations of IceCube-240412A
  33. GRB 240414A : MITSuME Akeno optical upper limits
  34. GRB 240414A: Redshift confirmation from GTC/OSIRIS+
  35. EP240413a: EP-WXT detection of a fast X-ray transient
  36. GRB 240414A : OHP/T193 redshift determination
  37. GRB 240414A : OHP/T193 optical counterpart detection
  38. GRB 240414A: Swift detection of a burst
  39. LIGO/Virgo/KAGRA S240413p: Updated Sky localization
  40. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  41. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  42. EP240408a: GSP optical upper limit
  43. GRB 240411B: CrAO/ZTSh optical observations
  44. GRB 240411B: Kinder observations with Lulin observatory
  45. LIGO/Virgo/Kagra S240413p: NED Galaxies in the Localization Volume
  46. LIGO/Virgo/KAGRA S240413p: Identification of a GW compact binary merger candidate
  47. GRB 240411B: HiPERCAM/GTC observation
  48. IceCube Alert 240412.23: Global MASTER-Net observations report
  49. GRB 240411B: Swift-BAT refined analysis
  50. GRB 240411B: Swift-XRT refined Analysis
  51. IceCube-240412A - IceCube observation of a high-energy neutrino candidate track-like event
  52. GRB 240411B: 1.3m DFOT Optical observations
  53. GRB 240411A: GRBAlpha detection
  54. GRB 240411B: OHP/T193 optical observations
  55. GRB 240405A: Glowbug gamma-ray detection
  56. GRB 240411B: Enhanced Swift-XRT position
  57. GRB 240411B: LCO optical afterglow detection
  58. GRB 240411B: Swift detection of a burst
  59. GRB 240408B: GRBAlpha detection
  60. GRB 240411A: Fermi GBM Final Real-time Localization
  61. EP240408A: MASTER optical observations
  62. EP240408a: GROND detection of a candidate counterpart
  63. EP240408a: Upper limits from GECAM-B Observation
  64. EP240408a: Swift follow-up observation
  65. EP240408a: BOOTES-6/DPRT optical upper limit
  66. X-ray transient EP240315a: second epoch e-MERLIN radio observations
  67. GRB 240405A: GRBAlpha detection
  68. EP240408a: EP-WXT detection of a fast X-ray transient
  69. Swift Trigger 1220736: detection of 4U 1543-62.
  70. GRB 240408B: AstroSat CZTI detection
  71. IceCube-240327B: GRANDMA/Kilonova-Catcher observations of 4FGL J0555.9+0030 and optical upper limits
  72. Fermi GRB 240408A: Global MASTER-Net observations report
  73. GRB 240408A: Fermi GBM Final Real-time Localization
  74. GRB 240407A: BALROG localization (Fermi Trigger 734144396 / GRB 240407042)
  75. GRB 240402C: CALET Gamma-Ray Burst Monitor detection
  76. Fermi GRB 240407A: Global MASTER-Net observations report
  77. GRB 240407A: Fermi GBM Final Real-time Localization
  78. Fermi-LAT gamma-ray observations of IceCube-240327B
  79. Fermi-LAT gamma-ray observations of IceCube-240327A
  80. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  81. Fermi GRB 240405B: Global MASTER-Net observations report
  82. GRB 240405B: Fermi GBM Final Real-time Localization
  83. GRB 240402C: Glowbug gamma-ray detection
  84. GRB 240405A: Fermi GBM Final Real-time Localization
  85. GRB 240402C: GRBAlpha detection
  86. GRB 240331A: GRBAlpha detection
  87. LXT 240402A/GRB 240402B: GECAM-C refined analysis
  88. Swift satellite resumes pointed science observations
  89. GRB 240403B: Glowbug gamma-ray detection
  90. GRB 240403A: Glowbug gamma-ray detection
  91. LXT 240402A/GRB 240402B: Glowbug gamma-ray detection
  92. X-ray transient LXT 240402A: WFST optical upper limits​
  93. Konus-Wind detection of LXT 240402A/GRB 240402B
  94. GRB/FXT 240402B: Kinder optical counterpart candidate
  95. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  96. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  97. GRB 240403A: Fermi GBM Detection
  98. X-ray transient LXT240402A: AST3-3 optical upper limits
  99. LXT 240402A: EP-FXT detection of the X-ray afterglow
  100. Fermi GRB 240404A: Global MASTER-Net observations report

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