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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"

21090 results found.

  1. GRB 240419B: optical afterglow from the NOT
  2. EP240414a: Near-IR observations with NIRES and WINTER
  3. Swift GRB 240419B: Global MASTER-Net observations report
  4. Swift GRB 240419A: Global MASTER-Net observations report
  5. GRB 240418A: Swift/UVOT Upper Limits
  6. GRB 240419A: REM NIR afterglow detection
  7. GRB 240411B: Swift/UVOT Detection
  8. GRB 240419A: VLT/UVES redshift of z = 5.178
  9. GRB 240419A: VLT optical afterglow detection
  10. Fermi trigger No 735089036: Global MASTER-Net observations report
  11. EP240416a: J-band observations with WINTER
  12. GRB 240418A: TSHAO Zeiss-1000 optical upper limit
  13. GRB 240418A: NOT optical upper limits
  14. GRB 240411A: GOTO early optical upper limits
  15. Swift GRB240418.85: Global MASTER-Net observations report
  16. EP240417a: EP-WXT detection of a fast X-ray transient
  17. Fermi GRB 240417A: Global MASTER-Net observations report
  18. LIGO/Virgo/KAGRA S240413p: X-ray upper limits from EP-WXT for the candidate AGN counterpart
  19. EP240414a: GSP detects optical candidate counterpart AT2024gsa
  20. LIGO/Virgo/KAGRA S240413p: DECam GW-MMADS candidates
  21. EP240414a: Pan-STARRS detects re-brightening of the candidate counterpart AT2024gsa
  22. LIGO/Virgo/KAGRA S240413p: historical ATLAS and ZTF observations of the candidate AGN counterpart
  23. LIGO/Virgo/KAGRA S240413p: STEP - T80S Search and Candidate Counterpart Identification
  24. EP240416A: MASTER optical observations
  25. EP240416a: Kinder optical counterpart candidate
  26. EP240416a: EP-WXT detection of a fast X-ray transient
  27. GRB 240414A: AbAO optical upprer limit
  28. GRB 240415A: Swift/UVOT Detection
  29. GRB 240414A: GAD Observatory, La Spezia, Italy ,upper limit
  30. GRB 240415A: Earliest optical followup with the Kinder observations
  31. GRB 240415B: Swift ToO observations
  32. GRB 240415B: Swift/BAT-GUANO Correction
  33. GRB 240415B: Swift/BAT-GUANO arcminute localization of a short burst
  34. GRB 240415A: OHP/T193 optical observations
  35. GRB 240415A: optical afterglow detection from the INAF Asiago Observatory
  36. GRB 240415A: SAO RAS optical observations
  37. Fermi GRB 240415A: Global MASTER-Net observations report
  38. GRB 240415A: Mondy optical transient detection
  39. GRB 240414A: Photometric observation from 2.2m CAHA
  40. GRB 240414A: Swift/UVOT Detection
  41. LXT 240402A/GRB 240402B: Swift follow-up observations
  42. GRB 240414A: Mondy optical observations
  43. X-ray transient EP 240414a - GTC spectroscopic observations
  44. GRB 240415A: Prompt Swift-XRT observations
  45. EP 240414a: NOT optical counterpart confirmation
  46. GRB240414A : J-band upper limits from WINTER
  47. GRB 240414A : OHP/T193 second epoch of optical follow-up and afterglow detection
  48. GRB 240414A: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  49. LIGO/Virgo/KAGRA S240413p: No Counterparts in DDOTI/OAN Optical Observations
  50. EP240413A: GOTO optical upper limits
  51. GRB 240414A: Skynet Optical Afterglow Observations
  52. Fermi trigger No 734754044: Global MASTER-Net observations report
  53. Swift GRB 240414A: Global MASTER-Net observations report
  54. EP240414a: Kinder optical counterpart candidate possibly associated with the galaxy SDSS J124601.99-094309.3
  55. Fermi-LAT gamma-ray observations of IceCube-240412A
  56. GRB 240414A : OHP/T193 redshift determination
  57. GRB 240414A : OHP/T193 optical counterpart detection
  58. LIGO/Virgo/KAGRA S240413p: Global MASTER-Net observations report
  59. LIGO/Virgo/KAGRA S240413p: Zwicky Transient Facility observations
  60. EP240408a: GSP optical upper limit
  61. GRB 240411B: CrAO/ZTSh optical observations
  62. GRB 240411B: Kinder observations with Lulin observatory
  63. LIGO/Virgo/Kagra S240413p: NED Galaxies in the Localization Volume
  64. GRB 240411B: HiPERCAM/GTC observation
  65. IceCube Alert 240412.23: Global MASTER-Net observations report
  66. GRB 240411B: 1.3m DFOT Optical observations
  67. GRB 240411B: OHP/T193 optical observations
  68. GRB 240411B: LCO optical afterglow detection
  69. EP240408A: MASTER optical observations
  70. EP240408a: Swift follow-up observation
  71. X-ray transient EP240315a: second epoch e-MERLIN radio observations
  72. EP240408a: EP-WXT detection of a fast X-ray transient
  73. IceCube-240327B: GRANDMA/Kilonova-Catcher observations of 4FGL J0555.9+0030 and optical upper limits
  74. Fermi GRB 240408A: Global MASTER-Net observations report
  75. Fermi GRB 240407A: Global MASTER-Net observations report
  76. Fermi-LAT gamma-ray observations of IceCube-240327B
  77. Fermi-LAT gamma-ray observations of IceCube-240327A
  78. Fermi GRB 240405B: Global MASTER-Net observations report
  79. LXT 240402A/GRB 240402B: GECAM-C refined analysis
  80. Swift satellite resumes pointed science observations
  81. X-ray transient LXT 240402A: WFST optical upper limits​
  82. IceCube-240327B: GRANDMA observations of 4FGL J0555.9+0030
  83. GRB/FXT 240402B: VLT/FORS2 optical afterglow candidate
  84. LXT 240402A: EP-FXT detection of the X-ray afterglow
  85. Fermi GRB 240404A: Global MASTER-Net observations report
  86. LXT 240402A: MASTER optical observations with AGN in error-box
  87. X-ray transient LXT 240402A: LEIA detection
  88. Fermi trigger No 733808041: Global MASTER-Net observations report
  89. Fermi GRB 240402A: Global MASTER-Net observations report
  90. X-ray transient EP240331a: Kinder optical upper limits
  91. X-ray transient EP240331A: GRANDMA-Kilonova catcher optical upper limit
  92. EP240331A: MASTER optical observations
  93. Transient EP240315a: J-band observations of AT2024eju with WIRC
  94. X-ray transient EP20240331a: MeerLICHT optical upper limits
  95. Integral GRB240401.69: Global MASTER-Net observations report
  96. Fermi trigger No 733366352: Global MASTER-Net observations report
  97. Fermi GRB 240329A: Global MASTER-Net observations report
  98. Fermi GRB 240328B: Global MASTER-Net observations report
  99. Fermi GRB 240328A: Global MASTER-Net observations report
  100. X-ray transient EP240315a: continued ATCA monitoring

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