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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"

12399 results found.

  1. Fermi-LAT gamma-ray observations of IceCube-241127A
  2. Fermi trigger No 754492985: Global MASTER-Net observations report
  3. Swift GRB241127.91: Global MASTER-Net OT detection
  4. IceCube Alert 241127.59: Global MASTER-Net observations report
  5. Swift GRB241127.91: Global MASTER-Net observations report
  6. Swift GRB241127.91: Global MASTER-Net OT detection
  7. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  8. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  9. EP241126a: Optical Upper limits with Kinder observations
  10. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  11. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  12. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  13. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  14. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  15. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  16. LIGO/Virgo/KAGRA S241125n: Upper limits from Konus-Wind observations
  17. EP241125a: Optical upper limit with Kinder observations
  18. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  19. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  20. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  21. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  22. LIGO/Virgo/KAGRA S241109bn: Upper limits from a two-week IceCube neutrino search
  23. GRB 241026A: VIRT Optical Upper Limit
  24. GRB 241025A: VIRT Optical Upper Limit
  25. Konus-Wind detection of GRB 241120A
  26. GRB241120A: OHP/T193 optical observations
  27. EP241021a and EP241026b: Keck/LRIS spectroscopic observations
  28. EP241119a: Optical upper limits with Kinder observations
  29. EP241119a: GIT optical upper limits
  30. EP241119a : J-band observations with WINTER
  31. Integral GRB241120.25: Global MASTER-Net observations report
  32. EP241119a: Global MASTER-Net observations report
  33. GRB 241112B: Mephisto further optical observations
  34. GRB 241115a: PRIME near-infrared upper limits
  35. LIGO/Virgo/KAGRA S241116cq: Upper limits from Swift/BAT-GUANO
  36. Fermi GRB 241118A: Global MASTER-Net observations report
  37. Fermi GRB 241117B: Global MASTER-Net observations report
  38. IceCube-Cascade 241116A: Upper limits from a search for additional neutrino events in IceCube
  39. Fermi GRB 241117A: Global MASTER-Net observations report
  40. GRB 241115A: Swift-XRT afterglow detection
  41. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  42. GRB 241115A: Mephisto upper limits
  43. GRB 241113B: Mephisto upper limits
  44. GRB 241115A: LCOGT Optical Upper Limits
  45. Fermi GRB 241115B: Global MASTER-Net observations report
  46. EP241115a: Global MASTER-Net observations report
  47. Swift GRB 241115A: Global MASTER-Net observations report
  48. Fermi GRB 241115A: Global MASTER-Net observations report
  49. GRB 241115A: Swift detection of a burst
  50. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  51. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  52. GRB 241113A: PRIME near-infrared upper limits
  53. Fermi GRB 241114A: Global MASTER-Net observations report
  54. EP241113a: Global MASTER-Net observations report
  55. GRB 241113B: J-band upper limit from WINTER
  56. GRB 241113A: J-band observations with WINTER
  57. EP241113a : J-band observations with WINTER
  58. GRB 241113B: Swift-XRT observations
  59. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  60. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  61. EP241113b: Global MASTER-Net observations report
  62. Fermi-LAT gamma-ray observations of IceCube-241113A
  63. EP241107a: SOAR upper limits
  64. GRB 241113A: Swift/UVOT Detection
  65. GRB 241112B: GMG Optical Upper Limit
  66. Swift GRB241113.33: Global MASTER-Net observations report
  67. Fermi trigger No 753166198: Global MASTER-Net observations report
  68. GRB 241105A: ATCA Radio Upper Limits
  69. GRB 241112B: AbAO optical upper limit
  70. GRB 241107A: GROWTH-India telescope optical upper limit
  71. IceCube Alert 241113.02: Global MASTER-Net observations report
  72. Fermi GRB 241112A: Global MASTER-Net observations report
  73. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  74. GRB 241112B: Swift-XRT afterglow detection
  75. GRB 241112B: Mephisto optical upper limits
  76. GRB 241112B: GOTO optical upper limits
  77. Fermi trigger No 752990530: Global MASTER-Net observations report
  78. GRB 241030B: TESS detection of optical counterpart
  79. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  80. Fermi trigger No 752878030: Global MASTER-Net observations report
  81. Integral GRB241109.89: Global MASTER-Net observations report
  82. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  83. EP241107a: AbAO optical upper limit
  84. LIGO/Virgo/KAGRA S241109bn: Upper limits from Fermi-GBM Observations
  85. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  86. LIGO/Virgo/KAGRA S241109bn: Global MASTER-Net observations report
  87. GRB 241108A: Swift-XRT observations
  88. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  89. GRB 241105a: PRIME near-infrared upper limits
  90. EP241107a: Global MASTER-Net observations report
  91. GRB 241105A: Swift/UVOT Detection
  92. EP241101a: CrAO ZTSH optical observations
  93. GRB 241104A: Swift-XRT observations
  94. GRB 240511A: LCO upper limits
  95. Fermi GRB 241105A: Global MASTER-Net observations report
  96. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  97. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  98. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  99. GRB 240821A: further radio observations with the VLA
  100. Fermi GRB 241104A: Global MASTER-Net observations report

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