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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"

21983 results found.

  1. GRB 240414A: Photometric observation from 2.2m CAHA
  2. GRB 240414A: Swift/UVOT Detection
  3. LXT 240402A/GRB 240402B: Swift follow-up observations
  4. GRB 240414A: Mondy optical observations
  5. X-ray transient EP 240414a - GTC spectroscopic observations
  6. GRB 240415A: Prompt Swift-XRT observations
  7. EP240413a: Upper limits from GECAM-B Observation
  8. EP 240414a: NOT optical counterpart confirmation
  9. GRB240414A : J-band upper limits from WINTER
  10. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  11. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  12. LIGO/Virgo/KAGRA S240413p: No Counterparts in DDOTI/OAN Optical Observations
  13. EP240413A: GOTO optical upper limits
  14. GRB 240414A: Skynet Optical Afterglow Observations
  15. Fermi trigger No 734754044: Global MASTER-Net observations report
  16. Swift GRB 240414A: Global MASTER-Net observations report
  17. EP240414a: Kinder optical counterpart candidate possibly associated with the galaxy SDSS J124601.99-094309.3
  18. Fermi-LAT gamma-ray observations of IceCube-240412A
  19. GRB 240414A : OHP/T193 redshift determination
  20. GRB 240414A : OHP/T193 optical counterpart detection
  21. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  22. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  23. EP240408a: GSP optical upper limit
  24. GRB 240411B: CrAO/ZTSh optical observations
  25. GRB 240411B: Kinder observations with Lulin observatory
  26. LIGO/Virgo/Kagra S240413p: NED Galaxies in the Localization Volume
  27. GRB 240411B: HiPERCAM/GTC observation
  28. IceCube Alert 240412.23: Global MASTER-Net observations report
  29. GRB 240411B: 1.3m DFOT Optical observations
  30. GRB 240411B: OHP/T193 optical observations
  31. GRB 240411B: LCO optical afterglow detection
  32. EP240408A: MASTER optical observations
  33. EP240408a: Upper limits from GECAM-B Observation
  34. EP240408a: Swift follow-up observation
  35. X-ray transient EP240315a: second epoch e-MERLIN radio observations
  36. EP240408a: EP-WXT detection of a fast X-ray transient
  37. IceCube-240327B: GRANDMA/Kilonova-Catcher observations of 4FGL J0555.9+0030 and optical upper limits
  38. Fermi GRB 240408A: Global MASTER-Net observations report
  39. Fermi GRB 240407A: Global MASTER-Net observations report
  40. Fermi-LAT gamma-ray observations of IceCube-240327B
  41. Fermi-LAT gamma-ray observations of IceCube-240327A
  42. LXT 240402A/GRB 240402B: rest-frame energetics from Konus-Wind observation
  43. Fermi GRB 240405B: Global MASTER-Net observations report
  44. LXT 240402A/GRB 240402B: GECAM-C refined analysis
  45. Swift satellite resumes pointed science observations
  46. X-ray transient LXT 240402A: WFST optical upper limits​
  47. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  48. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  49. LXT 240402A: EP-FXT detection of the X-ray afterglow
  50. Fermi GRB 240404A: Global MASTER-Net observations report
  51. LXT 240402A: MASTER optical observations with AGN in error-box
  52. X-ray transient LXT 240402A: LEIA detection
  53. Fermi trigger No 733808041: Global MASTER-Net observations report
  54. Fermi GRB 240402A: Global MASTER-Net observations report
  55. X-ray transient EP240331a: Kinder optical upper limits
  56. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  57. EP240331A: MASTER optical observations
  58. Transient EP240315a: J-band observations of AT2024eju with WIRC
  59. X-ray transient EP20240331a: MeerLICHT optical upper limits
  60. Integral GRB240401.69: Global MASTER-Net observations report
  61. Fermi trigger No 733366352: Global MASTER-Net observations report
  62. Fermi GRB 240329A: Global MASTER-Net observations report
  63. Fermi GRB 240328B: Global MASTER-Net observations report
  64. Fermi GRB 240328A: Global MASTER-Net observations report
  65. X-ray transient EP240315a: continued ATCA monitoring
  66. IceCube-240327B: No candidates from the Zwicky Transient Facility
  67. IceCube Alert 240327.68: Global MASTER-Net observations report
  68. X-ray transient EP 240315a: Second epoch Chandra observations
  69. Fermi trigger No 733097506: Global MASTER-Net observations report
  70. X-ray transient EP240315a: e-MERLIN radio observations
  71. X-ray transient EP240315a: Ondrejov D50 optical limit
  72. Transient EPW20240219aa: REM optical/NIR further observations
  73. Fermi trigger No 733092476: Global MASTER-Net observations report
  74. Fermi trigger No 732937833: Global MASTER-Net observations report
  75. Fermi GRB 240320A: Global MASTER-Net observations report
  76. Fermi trigger No 732657380: Global MASTER-Net observations report
  77. GRB 240318A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  78. X-ray transient EP240315a: ATCA detection of radio counterpart
  79. X-ray transient EP 240315a: Chandra observations
  80. X-ray transient EP240315a: GTC/HiPERCAM photometry
  81. X-ray transient EP240315a: MeerKAT radio detection
  82. X-ray transient EP240315a: GTC/OSIRIS spectroscopic redshift confirmation
  83. X-ray transient EP240315a: PRIME near infrared detection
  84. Swift satellite in safe mode
  85. X-ray transient EP240315a: EP-FXT detection of the X-ray afterglow
  86. Fermi GRB 240318A: Global MASTER-Net observations report
  87. GRB 240317B: Swift/BAT-GUANO arcminute localization of a burst
  88. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  89. Fermi GRB 240317B: Global MASTER-Net observations report
  90. Fermi GRB 240317A: Global MASTER-Net observations report
  91. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  92. X-ray transient EP240315a: VLT/X-shooter spectroscopic redshift of z = 4.859
  93. Fermi trigger No 732299243: Global MASTER-Net observations report
  94. AT2024eju: followup observations with Liverpool Telescope suggest a fading transient
  95. X-ray transient EP240315a: ATLAS detection of a possible optical counterpart AT2024eju
  96. Einstein Probe detected of a fast X-ray transient EP240315a
  97. Fermi GRB 240314A: Global MASTER-Net observations report
  98. GRB 240310A: MASTER OT J200702.72-263928.7 inside 3sigma
  99. Fermi trigger No 731839490: Global MASTER-Net observations report
  100. Fermi-LAT gamma-ray observations of IceCube-240307A

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