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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"

22193 results found.

  1. Swift GRB241127.91: Global MASTER-Net observations report
  2. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  3. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  4. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345)
  5. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations (duplicate submission of 38345).
  6. LIGO/Virgo/KAGRA S241125n: EP-FXT follow-up observations
  7. EP241126a: Optical Upper limits with Kinder observations
  8. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  9. EP241126a: GSP detects optical counterpart
  10. EP241126a: TRT optical counterpart detection
  11. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  12. EP241126a: EP detection of a fast X-ray transient
  13. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  14. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  15. Trigger_18947: Swift ToO observations (retracted)
  16. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  17. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  18. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  19. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  20. Konus-Wind detection of GRB 241115D / EP 241115a
  21. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  22. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  23. GRB 241026A: radio detection with the VLA
  24. EP241125a: Optical upper limit with Kinder observations
  25. EP241125a: EP detection of an X-ray transient
  26. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  27. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  28. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  29. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  30. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  31. GRB 241113B: SVOM/VT optical afterglow observations
  32. GRB 241105A: ATCA radio detection
  33. GRB241120A: OHP/T193 optical observations
  34. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  35. EP trigger ID 01709065118: Keck/LRIS spectroscopic observations
  36. EP-WXT trigger 01709018832: Lick/Kast spectroscopy with the 3 m Shane telescope
  37. GRB 241120A: Mondy and AbAO optical observations
  38. EP241119a: Optical upper limits with Kinder observations
  39. EP241119a: GIT optical upper limits
  40. GRB 241113A: Possible ATCA Radio detection
  41. EP241119a : J-band observations with WINTER
  42. Integral GRB241120.25: Global MASTER-Net observations report
  43. EP241119a: Global MASTER-Net observations report
  44. EP241119a: EP detection of a fast X-ray transient
  45. GRB 241112B: Mephisto further optical observations
  46. GRB 241030A: J-band observations
  47. GRB 241115a: PRIME near-infrared upper limits
  48. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  49. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  50. Fermi GRB 241118A: Global MASTER-Net observations report
  51. Fermi GRB 241117B: Global MASTER-Net observations report
  52. GRB 241115B: Swift/BAT-GUANO localization skymap of a long burst
  53. Fermi GRB 241117A: Global MASTER-Net observations report
  54. GRB 241115A: Swift-XRT afterglow detection
  55. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  56. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  57. Fermi GRB 241115B: Global MASTER-Net observations report
  58. EP241115a: Global MASTER-Net observations report
  59. EP241115a: EP detection of a fast X-ray transient
  60. EP241113a: No Detection in Fermi-GBM Observations
  61. Swift GRB 241115A: Global MASTER-Net observations report
  62. Fermi GRB 241115A: Global MASTER-Net observations report
  63. EP 241113a: LBT possible optical counterpart
  64. GRB 241113B: KAIT Optical Afterglow Candidate
  65. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  66. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  67. GRB 241113A: PRIME near-infrared upper limits
  68. Fermi GRB 241114A: Global MASTER-Net observations report
  69. EP241113a: Global MASTER-Net observations report
  70. GRB 241113B: J-band upper limit from WINTER
  71. GRB 241113A: J-band observations with WINTER
  72. EP241113a : J-band observations with WINTER
  73. GRB 241030A: LCO optical observation
  74. GRB 241113B: Swift-XRT observations
  75. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  76. GRB 241113A: KAIT optical observations
  77. EP241113b: Global MASTER-Net observations report
  78. Fermi-LAT gamma-ray observations of IceCube-241113A
  79. EP241113a: EP on-board trigger and autonomous follow-up observation
  80. EP241107a: SOAR upper limits
  81. GRB 241113A: Swift/UVOT Detection
  82. GRB 241113A: REM detection of the optical/NIR afterglow
  83. GRB 241113B: Swift ToO observations
  84. GRB 241113A: LCO optical observations
  85. GRB241113A: LCOGT (40-cm) optical counterpart detection
  86. Swift GRB241113.33: Global MASTER-Net observations report
  87. Fermi trigger No 753166198: Global MASTER-Net observations report
  88. GRB 241105A: ATCA Radio Upper Limits
  89. GRB 241112B: AbAO optical upper limit
  90. GRB 241107A: GROWTH-India telescope optical upper limit
  91. IceCube Alert 241113.02: Global MASTER-Net observations report
  92. Fermi GRB 241112A: Global MASTER-Net observations report
  93. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  94. GRB 241112B: Swift-XRT afterglow detection
  95. GRB 241112B: SVOM/VT afterglow detection
  96. GRB 241112B: Mephisto optical upper limits
  97. GRB 241112B: GOTO optical upper limits
  98. GRB 241112B: Swift ToO observations
  99. EP241107a: EP-FXT follow-up observations
  100. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume

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