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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

342 results found.

  1. LIGO/Virgo S190924h: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  2. LIGO/Virgo S190923y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  3. IceCube-190922A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  4. HAWC-190916A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  5. LIGO/Virgo S190915ak: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  6. LIGO/Virgo S190910h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  7. LIGO/Virgo S190910d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  8. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  9. LIGO/Virgo S190828l: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  10. LIGO/Virgo S190828j: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  11. Fermi GBM-190816: Location-dependent upper limits from INTEGRAL/SPI-ACS prompt observation
  12. IceCube-190819A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  13. HAWC-190806A: upper limits from INTEGRAL SPI-ACS and IBIS prompt observation
  14. IceCube 190730A: one weakly associated counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  15. GRB 190719C: optical afterglow confirmation
  16. Fermi-LAT Gamma-ray Observations of IceCube-190712A
  17. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  18. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  19. LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
  20. INTEGRAL observations of the events in the GWTC-1 catalog
  21. GRB 181201A: a long GRB detected by INTEGRAL
  22. GRB 180809A: further Swift/XRT observations
  23. GRB 180728A: VLT/X-shooter redshift of a nearby energetic GRB
  24. GRB 180427A: AstroSat CZTI detection
  25. LIGO/Virgo G297595: NIR Observations following GW170814
  26. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  27. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  28. LIGO/Virgo G298936: Astrosat CZTI upper limits
  29. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  30. LIGO/Virgo G298048: Chandra X-ray observations
  31. GRB170730A detecetd by INTEGRAL. Refined analysis
  32. GRB 170522A: Swift-XRT observations
  33. GRB 170318B: Swift-BAT refined analysis
  34. LIGO/Virgo G275697: SVOM/Mini-GWAC observations of the initial skymap
  35. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  36. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  37. GRB 160401A: a long GRB detected by INTEGRAL
  38. LIGO/Virgo G184098: Fermi-GBM ground-based follow-up
  39. GRB 150912A: A long GRB detected by INTEGRAL
  40. SGR 1E 1841-045 (Swift trigger 649113): Terskol upper limit
  41. Fermi GBM triggers bn150715759 and bn150715817 are not due to GRBs
  42. Trigger 649113: Swift detection of SGR 1E 1841-045
  43. Swift trigger 642453 is not an astrophysical source
  44. Swift Trigger 629693: probably not real
  45. Swift detection of 4U 1700+24 (= V934 Her)
  46. GRB 140710B: a long GRB detected with INTEGRAL
  47. GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8
  48. GRB 140629A: Swift detection of a burst with an optical counterpart
  49. Swift detection of a bright X-ray source in M31
  50. GRB 131108A: AGILE/GRID observation
  51. Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
  52. GRB 130907A: INTEGRAL/SPI-ACS light curve
  53. GRB 130609B: Swift/UVOT Observations
  54. GRB 130513A: a long GRB detected by INTEGRAL
  55. Swift-BAT refined analysis of SGR 1E 1841-045 (Trigger=543763)
  56. Trigger 543763: SGR 1E 1841-045: Swift detection of a soft gamma repeater burst (aka Kes 73)
  57. GRB 121102A : a long GRB detected by INTEGRAL
  58. GRB 121027A: Swift-XRT refined Analysis
  59. Swift-BAT refined analysis of 1E 1841-045 (Trigger=526660)
  60. Trigger 526660: Swift detection of 1 E 1841-045 (aka Kes 73)
  61. GRB 120624B: Swift-XRT observations
  62. GRB 120512A: A long GRB detected by INTEGRAL
  63. Fermi/GBM detection of a burst from the magnetar 1E 2259+5
  64. GRB 111212A: Swift-BAT refined analysis
  65. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  66. SGR 1E 1841-045: early optical limit by "Pi of the Sky"
  67. SGR 1E 1841-045: Swift-BAT refined analysis
  68. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  69. GRB 110625A: Fermi GBM and LAT observations
  70. SGR 1E 1841-045: Swift-BAT refined analysis
  71. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  72. ICSP VLF observation of multiple SGR-like bursts from 1E 1841-045 on Feb. 9, 2011
  73. Fermi GBM detection of an SGR-like burst
  74. Swift-BAT refined analysis of outburst from 1E 1841-04.5
  75. Fermi GBM detection of a burst from 1E 1841-045
  76. SGR-like outburst from the magnetar 1E 1841-04.5
  77. GRB 110112B: A short GRB detected by INTEGRAL
  78. An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
  79. GRB 100316D: Pre-burst emission measured by BAT
  80. Trigger 381434: Swift detection of a possible burst
  81. GRB 090709A: Quasiperiodic variations in the BAT light curve
  82. GRB 090708: ROTSE-III Optical Limits
  83. XRF 090702: Swift-XRT refined analysis
  84. A bright burst from AXP 1E 1547.0-5408/SGR J1550-5418
  85. SGR J1550-5418
  86. IBAS Alert N. 5442 is not a GRB
  87. Suzaku ToO Observation of AXP 1E 1547.0-5408
  88. Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
  89. GRB 090111: Swift UVOT Upper Limits
  90. GRB 081222: Swift XRT refined analysis
  91. INTEGRAL ToO observation of the AXP 1E 1547.0-5408
  92. AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
  93. GRB080818B: GLAST Burst Monitor detection
  94. GRB 080520: Swift XRT Refined Analysis
  95. GRB 080330A: ROTSE-III Detection of Optical Counterpart
  96. GRB 080205: Swift XRT refined analysis
  97. GRB 080121: Upper limit on X-ray afterglow
  98. GRB080120: Swift XRT position
  99. Swift XRT follow-up observations of GRB071008
  100. GRB 071003: XRT refined analysis

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