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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').
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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"

23611 results found.

  1. GRB 241029A: TRT optical afterglow candidate detection
  2. GRB 241026A: TNOT optical counterpart detection
  3. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  4. GRB 241025A: further SAO RAS optical observations
  5. GRB 241026A: BTA and Zeiss-1000 optical observations
  6. GRB 241026A: SVOM/GRM observation
  7. EP241026B: GROWTH-India Telescope optical upper limit
  8. GRB 241025A: Swift/UVOT Detection
  9. GRB 241026A: GROWTH-India Telescope optical observations
  10. GRB 241026A: J-band observations with WINTER
  11. GRB 241025A: SAO RAS optical observations
  12. GRB 241026A: Las Cumbres optical detection
  13. GRB 241025A: Mondy optical observations
  14. EP241021a: SOAR observations of the optical counterpart
  15. EP241021a: further SAO RAS optical observations
  16. EP 241026b: LBT optical observations
  17. EP241021a: e-MERLIN radio observation
  18. GRB 241026A: Enhanced Swift-XRT position
  19. EP241026b: EP detection of a fast X-ray transient
  20. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  21. GRB 241026A: SAO RAS observations of possible optical afterglow
  22. GRB 241026A: Swift detection of a burst
  23. GRB241025A: 1.3m DFOT optical afterglow detection
  24. EP241021a: optical follow-up observations with Xinglong Observatory
  25. GRB 241025A: GROWTH-India Telescope optical observations
  26. GRB 241025A: COLIBRÍ Detection of the Afterglow
  27. GRB 241025A: Fermi GBM Observation
  28. IPN triangulation of GRB 241022A (short/hard)
  29. EP 241021a: Swift-XRT observations
  30. EP241021a: optical follow-up observations with the Liverpool Telescope
  31. GRB 241025A : SVOM/VT optical afterglow observations
  32. EP241021a: Liverpool Telescope optical follow-up observations
  33. GRB 241025A: Enhanced Swift-XRT position
  34. GRB 241025A: DDOTI Afterglow detection
  35. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  36. GRB 241025A: TRT optical afterglow observation
  37. GRB 241025A: Swift detection of a burst with an optical counterpart
  38. EP241021a: GTC OSIRIS+ spectroscopy of the optical counterpart
  39. GRB 241001A: ATCA radio observations
  40. GRB 241010A: VIRT Optical Upper Limit
  41. EP241021a: SAO RAS optical observations
  42. EP241021a: KAIT optical observations
  43. IPN triangulation of GRB 241021A (long)
  44. EP241021a: 1.3m DFOT Optical observations
  45. EP241021a: Optical upper limits with Kinder observations
  46. EP241021a: TRT optical observations
  47. GRB 241018A: SVOM/C-GFT optical observations
  48. EP241021a: NOT likely optical counterpart
  49. GRB241017A: 1.3m DFOT optical upper limit
  50. GRB 241018A: 1.3m DFOT Optical upper limit
  51. EP241021a: GOTO optical upper limits
  52. EP241021a: EP detection of a fast X-ray transient
  53. Konus-Wind detection of GRB 241018A
  54. GRB 241018A/sb24101802: Mephisto optical upper limit
  55. GRB 241017A/sb24101702: Mephisto optical upper limit
  56. GRB 241018A: Mondy optical upper limit
  57. GRB 241018A: GROWTH-India telescope optical upper limit
  58. GRB241018A: XingLong Optical Upper Limit
  59. GRB 241018A: Swift-XRT observations
  60. GRB 241018A: REM optical/NIR upper limits
  61. GRB 241018A: NOT optical observations
  62. GRB 241017A: SVOM/VT follow-up and optical upper limit
  63. GRB 241018A: SVOM/VT follow-up and optical candidate
  64. GRB 241018A: LCO/0.4m optical upper limits
  65. GRB 241006A: VIRT Optical Upper Limit
  66. GRB 240727A: VIRT Optical Upper Limit
  67. GRB 241018A: X-ray afterglow candidate observed by MXT
  68. GRB 241017A: Swift-XRT observations
  69. GRB241017a: Liverpool Telescope observations of XRT uncatalogued sources
  70. GRB 241017A: GROWTH-India Telescope optical upper limit
  71. GRB241017A: TOO Observations by SVOM/MXT
  72. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  73. GRB 241017A: J-band upper limit from WINTER
  74. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  75. GRB 240916A: radio detection with the VLA
  76. GRB241013A: REM observations
  77. GRB 241009A: LCO optical upper limits
  78. LIGO/Virgo/KAGRA S241011k: NED Galaxies in the Localization Volume
  79. LIGO/Virgo/KAGRA S241011k: Identification of a GW compact binary merger candidate
  80. GRB 241009A: GRANDMA optical upper limits
  81. GRB 241009A: Swift-XRT afterglow detection
  82. GRB 241010A: JinShan optical observations and potential host galaxy
  83. GRB 241006A: ATCA Radio Upper Limits
  84. LIGO/Virgo/KAGRA S241007bw: Updated Sky localization
  85. GRB 241010A: J-band observations with WINTER
  86. GRB 241010A: Enhanced Swift-XRT position
  87. GRB 241010A: LCO optical observations
  88. GRB 241010A: Swift detection of a burst with an optical counterpart
  89. LIGO/Virgo/KAGRA S241009em: Identification of a GW compact binary merger candidate
  90. GRB 241002B: Swift-XRT afterglow detection
  91. LIGO/Virgo/KAGRA S241009an: Identification of a GW compact binary merger candidate
  92. GRB 241002A: NOT optical upper limits
  93. LIGO/Virgo/KAGRA S241009l: Identification of a GW compact binary merger candidate
  94. IceCube-241006A: No candidates from the Zwicky Transient Facility
  95. GRB 241006A: GRANDMA optical upper limits
  96. GRB 241002B: PRIME near-infrared detection in 3rd epoch
  97. GRB 240910A: LBT optical observations
  98. GRB 241006A: PRIME near-infrared upper limits
  99. GRB 241006A: Swift/UVOT Upper Limits
  100. GRB 241006A: SVOM/VT follow-up and optical upper limit

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