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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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subject:"Swift"
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submitter:"Judith Racusin"

23611 results found.

  1. GRB 241209B: Swift-XRT afterglow detection
  2. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  3. EP241208a: Optical upper limit with Kinder observations
  4. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  5. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  6. GRB 241209D: Fermi GBM Observation
  7. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  8. GRB 241209D: COLIBRÍ detection of the afterglow
  9. GRB 241209A: COLIBRÍ Optical Upper Limit
  10. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  11. GRB 241209A: GRANDMA/TAROT upper limit
  12. GRB 241209A: REM optical/NIR observations
  13. GRB 241209D: Enhanced Swift-XRT position
  14. GRB 241209D: Swift detection of a burst
  15. GRB 241209A: Enhanced Swift-XRT position
  16. GRB 241114B: cubesat Avion detection
  17. GRB 241209A: VLT optical observations
  18. GRB 241209A: GOTO optical upper limits
  19. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  20. EP241208a: EP detection of a fast X-ray transient
  21. GRB 241209A: Swift detection of a short burst
  22. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  23. GRB 241206A: DDOTI Upper Limit on the Afterglow
  24. EP241206a: EP detection of a fast X-ray transient
  25. GRB 241206A: Swift/BAT-GUANO localization skymap of a burst
  26. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  27. EP241201a: 1.6m Mephisto Optical Upper Limits
  28. GRB 241204A: COLIBRÍ Optical Upper Limit
  29. EP241202b: KAIT optical upper limit
  30. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  31. GRB 241204A: DDOTI Upper Limits on the Afterglow
  32. GRB 241128A : RAPAS follow-up observations
  33. IceCube-241127A: No transient candidates from the Zwicky Transient Facility
  34. EP241202b: Kinder optical counterpart candidate
  35. GRB 241113B : RAPAS follow-up observation
  36. EP241201a: BOOTES-5 optical upper limit
  37. EP241202b: EP detection of a fast X-ray transient
  38. EP241201a: NOT optical observations
  39. IPN triangulation of GRB 241130A
  40. GRB 241130A: EIRSAT-1 GMOD Detection
  41. GRB 241128A: Swift/UVOT Upper Limits
  42. GRB 241129A: Swift/BAT-GUANO localization skymap of a burst
  43. EP241201a: Kinder optical counterpart candidate
  44. LIGO/Virgo/KAGRA S241102br: GRAWITA wide-field optical observations
  45. EP241126a: 1.6m Mephisto Optical Upper Limits
  46. LIGO/Virgo/KAGRA S241201ac: Identification of a GW compact binary merger candidate
  47. IPN triangulation of GRB 241128B
  48. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  49. GRB 241128A: AbAO optical upper limit
  50. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  51. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  52. GRB 241128A: Swift-BAT refined analysis
  53. GRB 241127A: PRIME near-infrared detection
  54. GRB 241128A: Mondy optical observations
  55. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  56. Swift-XRT observations of IceCube -241127A
  57. EP241126a: SVOM/VT observations
  58. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate
  59. GRB 241128A: Enhanced Swift-XRT position
  60. GRB 241128A: NOT optical observations
  61. GRB 241128A: LCO optical detection
  62. GRB 241128A: Swift-XRT afterglow detection
  63. GRB 241128A: Swift detection of a burst
  64. GRB 241127A: GRANDMA and Kilonova-Catcher optical afterglow detections
  65. GRB 241127A: Swift/UVOT Detection
  66. GRB 241127A: SVOM/GRM observation
  67. GRB 241127A: Enhanced Swift-XRT position
  68. GRB 241127A: LCOGT (40-cm) optical counterpart detection
  69. EP241126a: WFST Observations
  70. LIGO/Virgo/KAGRA S241125n: Update on Coincidence False Alarm Method
  71. GRB 241127A: Swift detection of a burst with an optical counterpart
  72. Swift GRB241127.91: Global MASTER-Net OT detection
  73. LIGO/Virgo/KAGRA S241125n: Preliminary flux estimate and spectral analysis of the Swift/BAT-GUANO candidate counterpart
  74. LIGO/Virgo/KAGRA S241125n: Swift-UVOT Upper Limits
  75. LIGO/Virgo/KAGRA S241127aj: NED Galaxies in the Localization Volume
  76. EP241126a: Optical Upper limits with Kinder observations
  77. IPN triangulation of GRB 241114B
  78. EP trigger ID 01709122294: 1.6m Mephisto multi-band optical observations
  79. EP241126a: TRT optical counterpart detection
  80. LIGO/Virgo/KAGRA S241127aj: Identification of a GW compact binary merger candidate
  81. EP241126a: EP detection of a fast X-ray transient
  82. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on Optical Counterparts to Two of the Swift/XRT Sources
  83. LIGO/Virgo/KAGRA S241125n: SAGUARO follow-up observations with the MMT
  84. LIGO/Virgo/KAGRA S241125n: DDOTI Optical Upper Limits
  85. LIGO/Virgo/KAGRA S241125n: Gaoyazi/GOT optical observations
  86. LIGO/VIRGO/KAGRA S241125n: GROWTH-India telescope optical observations
  87. LIGO/Virgo S241125n: Swift XRT observations, 5 X-ray sources
  88. LIGO/Virgo/KAGRA S241125n: HCT upper limit
  89. GRB 241026A: radio detection with the VLA
  90. EP241125a: Optical upper limit with Kinder observations
  91. EP241125a: EP detection of an X-ray transient
  92. LIGO/Virgo/KAGRA S241125n: COLIBRÍ Upper Limits on a Optical Counterpart at the BAT Position
  93. LIGO/Virgo/KAGRA S241125n: Upper limits from Fermi-GBM Observations
  94. LIGO/Virgo/KAGRA S241125n: Kinder optical upper limit in the BAT error region
  95. LIGO/Virgo/KAGRA S241125n: No counterpart candidates in INTEGRAL SPI-ACS prompt observation, comparisong with Swift/BAT counterpart
  96. LIGO/Virgo/KAGRA S241125n: Swift/BAT-GUANO candidate counterpart
  97. GRB 241120A: GRBAlpha detection
  98. LIGO/Virgo/KAGRA S241125n: Identification of a GW compact binary merger candidate
  99. LIGO/Virgo/KAGRA S241122a: Identification of a GW compact binary merger candidate
  100. IPN triangulation of GRB 241117A

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