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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"

12390 results found.

  1. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  2. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  3. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  4. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  5. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  6. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  7. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  8. EP241125a: Optical upper limit with Kinder observations
  9. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  10. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  11. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  12. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  13. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  14. GRB 241026A: VIRT Optical Upper Limit
  15. GRB 241025A: VIRT Optical Upper Limit
  16. Konus-Wind detection of GRB 241120A
  17. GRB241120A: OHP/T193 optical observations
  18. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  19. EP241119a: Optical upper limits with Kinder observations
  20. EP241119a: GIT optical upper limits
  21. EP241119a : J-band observations with WINTER
  22. Integral GRB241120.25: Global MASTER-Net observations report
  23. EP241119a: Global MASTER-Net observations report
  24. GRB 241112B: Mephisto further optical observations
  25. GRB 241115a: PRIME near-infrared upper limits
  26. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  27. Fermi GRB 241118A: Global MASTER-Net observations report
  28. Fermi GRB 241117B: Global MASTER-Net observations report
  29. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  30. Fermi GRB 241117A: Global MASTER-Net observations report
  31. GRB 241115A: Swift-XRT afterglow detection
  32. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  33. GRB 241115A: Mephisto upper limits
  34. GRB 241113B: Mephisto upper limits
  35. GRB 241115A: LCOGT Optical Upper Limits
  36. Fermi GRB 241115B: Global MASTER-Net observations report
  37. EP241115a: Global MASTER-Net observations report
  38. Swift GRB 241115A: Global MASTER-Net observations report
  39. Fermi GRB 241115A: Global MASTER-Net observations report
  40. GRB 241115A: Swift detection of a burst
  41. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  42. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  43. GRB 241113A: PRIME near-infrared upper limits
  44. Fermi GRB 241114A: Global MASTER-Net observations report
  45. EP241113a: Global MASTER-Net observations report
  46. GRB 241113B: J-band upper limit from WINTER
  47. GRB 241113A: J-band observations with WINTER
  48. EP241113a : J-band observations with WINTER
  49. GRB 241113B: Swift-XRT observations
  50. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  51. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  52. EP241113b: Global MASTER-Net observations report
  53. Fermi-LAT gamma-ray observations of IceCube-241113A
  54. EP241107a: SOAR upper limits
  55. GRB 241113A: Swift/UVOT Detection
  56. GRB 241112B: GMG Optical Upper Limit
  57. Swift GRB241113.33: Global MASTER-Net observations report
  58. Fermi trigger No 753166198: Global MASTER-Net observations report
  59. GRB 241105A: ATCA Radio Upper Limits
  60. GRB 241112B: AbAO optical upper limit
  61. GRB 241107A: GROWTH-India telescope optical upper limit
  62. IceCube Alert 241113.02: Global MASTER-Net observations report
  63. Fermi GRB 241112A: Global MASTER-Net observations report
  64. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  65. GRB 241112B: Swift-XRT afterglow detection
  66. GRB 241112B: Mephisto optical upper limits
  67. GRB 241112B: GOTO optical upper limits
  68. Fermi trigger No 752990530: Global MASTER-Net observations report
  69. GRB 241030B: TESS detection of optical counterpart
  70. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  71. Fermi trigger No 752878030: Global MASTER-Net observations report
  72. Integral GRB241109.89: Global MASTER-Net observations report
  73. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  74. EP241107a: AbAO optical upper limit
  75. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  76. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  77. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  78. GRB 241108A: Swift-XRT observations
  79. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  80. GRB 241105a: PRIME near-infrared upper limits
  81. EP241107a: Global MASTER-Net observations report
  82. GRB 241105A: Swift/UVOT Detection
  83. EP241101a: CrAO ZTSH optical observations
  84. GRB 241104A: Swift-XRT observations
  85. GRB 240511A: LCO upper limits
  86. Fermi GRB 241105A: Global MASTER-Net observations report
  87. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  88. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  89. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  90. GRB 240821A: further radio observations with the VLA
  91. Fermi GRB 241104A: Global MASTER-Net observations report
  92. EP241101a: EP-FXT observations update
  93. EP241103a: GIT optical upper limit
  94. Fermi trigger No 752365806: Global MASTER-Net observations report
  95. EP241103a: GOTO optical upper limit
  96. EP241101a: Possible detection of an optical counterpart with FTW
  97. EP241101a: Optical upper limits with Kinder observations
  98. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  99. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  100. EP241103a: GSP optical upper limit

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