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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"
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21112 results found.

  1. LIGO/Virgo S200105ae: More candidates from the Zwicky Transient Facility
  2. LIGO/Virgo S200115j: Swift/UVOT observations of Swift/XRT S200115j_X136
  3. LIGO/Virgo S200114f: More candidates from the Zwicky Transient Facility
  4. IceCube-200117A: Upper limits from Fermi-GBM Observations
  5. LIGO/Virgo S200114f: No transients found in J-GEM observations of nearby galaxies
  6. IceCube Alert 200117.46: Global MASTER-Net observations report
  7. LIGO/Virgo S200115j: Swift-XRT sources
  8. LIGO/Virgo S200115j: Upper limits from CALET observations.
  9. LIGO/Virgo S200115j: No notable candidates in GOTO imaging
  10. LIGO/Virgo S200114f: Upper Limits from Wide-Field Infrared Search with Palomar Gattini-IR
  11. GRB 200115A: DDOTI/OAN optical observations report
  12. LIGO/Virgo S200114f: Possible X-ray transient
  13. LIGO/Virgo S200112r : No significant candidates in TAROT - FRAM - GRANDMA observations.
  14. LIGO/Virgo S200114f: Swift-XRT sources and observations
  15. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  16. LIGO/Virgo S200116ah: Global MASTER-Net observations report
  17. Baksan Neutrino Observatory Alert 200116.22: Global MASTER-Net observations report
  18. Baksan Neutrino Observatory Alert 200116.21: Global MASTER-Net observations report
  19. GRB 200115A: Swift-BAT refined analysis
  20. LIGO/Virgo S200115j: no counterpart candidates in the Swift/BAT observations
  21. LIGO/Virgo S200115j: No counterpart candidates in Fermi-LAT observations
  22. LIGO/Virgo S200115j: Upper limits from Fermi-GBM Observations
  23. GRB 200115A: Nanshan-0.6m optical upper limit
  24. GRB 200115A: Swift detection of a burst
  25. Swift GRB200115.49: Global MASTER-Net observations report
  26. LIGO/Virgo S200115j: upper limits from AGILE/GRID observations
  27. LIGO/Virgo S200114f: No counterpart in targeted WHT/ACAM imaging
  28. LIGO/Virgo S200115j: Candidates from the Zwicky Transient Facility
  29. LIGO/Virgo S200115j: INTEGRAL was inactive at the time of the event
  30. LIGO/Virgo S200115j: upper limits from AGILE/MCAL observations
  31. LIGO/Virgo S200114f: Upper limits from CALET observations.
  32. LIGO/Virgo S200115j: Coverage and upper limits from MAXI/GSC observations
  33. LIGO/Virgo S200115j: No counterpart candidates in HAWC observations
  34. LIGO/Virgo S200115j: Global MASTER-Net observations report
  35. GRB 200114A: DDOTI/OAN optical observations report
  36. LIGO/Virgo S200114f: Candidates from SAGUARO observations
  37. LIGO/Virgo S200114f: No Counterparts in DDOTI/OAN Optical Observations
  38. LIGO/Virgo S200114f: upper limits from AGILE-GRID observations
  39. LIGO/Virgo S200114f: no counterpart candidates in the Swift/BAT observations
  40. IceCube-200109A: Candidate Counterparts from the Zwicky Transient Facility
  41. LIGO/Virgo S200114f: No counterpart candidates in Fermi-LAT observations
  42. LIGO/Virgo S200114f: Candidates from the Zwicky Transient Facility
  43. LIGO/Virgo S200112r: Upper limits from CALET observations
  44. LIGO/Virgo S200114f: Upper limits from Fermi-GBM Observations
  45. LIGO/Virgo S200114f: Coverage and upper limits from MAXI/GSC observations
  46. Fermi trigger No 600666048: Global MASTER-Net observations report
  47. LIGO/Virgo S200114f: No counterpart candidates in HAWC observations
  48. LIGO/Virgo S200114f: Global MASTER-Net observations report
  49. LIGO/Virgo S200112r: Upper limits from Insight-HXMT/HE observations
  50. Fermi-LAT Gamma-ray Observations of IceCube-200109A and detection of a possible new gamma-ray source, Fermi J1055.8+1034
  51. LIGO/Virgo 200112r: No counterpart candidates in Fermi-LAT observations
  52. LIGO/Virgo S200112r: upper limits from AGILE/GRID observations
  53. LIGO/Virgo S200112r: upper limits from AGILE/MCAL observations
  54. LIGO/Virgo S200112r: INTEGRAL was inactive at the time of the event
  55. LIGO/Virgo S200112r: Coverage and upper limits from MAXI/GSC observations
  56. LIGO/Virgo S200112r: No counterpart candidates in HAWC observations
  57. LIGO/Virgo S200112r: Global MASTER-Net observations report
  58. Fermi trigger No 600525396: Global MASTER-Net observations report
  59. Fermi trigger No 600448273: Global MASTER-Net observations report
  60. IceCube-200109A: Swift-XRT and UVoT Follow-up Observations
  61. ANTARES 200108A: No detection by Swift-XRT
  62. IceCube-200109A: INTEGRAL was inactive at the time of the event
  63. IceCube-200109A: Upper limits from Fermi-GBM Observations
  64. IceCube Alert 200109.99: Global MASTER-Net observations report
  65. IceCube Alert 200109.99: Global MASTER-Net observations report
  66. GRB 200107B: Swift/UVOT Observations
  67. Swift follow-up observations of IceCube-200107A: Identification of X-ray high state for 4FGL J0955.1+3551
  68. GRB 200109A: Swift/UVOT Upper Limits
  69. LIGO/Virgo S200105ae : No significant candidates in TAROT - FRAM - GRANDMA observations.
  70. Fermi-LAT ANTARES coincidence /ANTARES alert 200108.39: MASTER alert and inspect observation
  71. Fermi trigger No 600227156: Global MASTER-Net observations report
  72. Swift GRB200109.07: Global MASTER-Net observations report
  73. Fermi-LAT ANTARES coincidence: Upper limits from Fermi-GBM Observations
  74. LIGO/Virgo S200105ae: Candidates from the Zwicky Transient Facility
  75. Swift GRB 200107B: Global MASTER-Net observations report
  76. Fermi-LAT Gamma-ray Observations of IceCube-200107A
  77. IceCube-200107A: No candidates from the Zwicky Transient Facility
  78. IceCube-200107A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  79. LIGO/Virgo S200105ae: Upper limits from CALET observations.
  80. LIGO/Virgo S200105ae: Upper Limits from the Zwicky Transient Facility
  81. Swift GRB200107.81: Global MASTER-Net OT detection
  82. Swift GRB200107.81: Global MASTER-Net observations report
  83. IceCube-200107A: Upper limits from Fermi-GBM Observations
  84. LIGO/Virgo 200105ae: No counterpart candidates in Fermi-LAT observations
  85. LIGO/Virgo S200105ae: Coverage and upper limits from MAXI/GSC observations
  86. LIGO/Virgo S200105ae: No counterpart candidates in HAWC observations
  87. LIGO/Virgo S200105ae: no counterpart candidates in the Swift/BAT observations
  88. LIGO/Virgo S200105ae: Global MASTER-Net observations report
  89. LIGO/Virgo S200105ae: Upper limits from Fermi-GBM Observations
  90. LIGO/Virgo S200105ae: We have issued GCN Notices to support automated processing
  91. LIGO/Virgo S200105ae: A subthreshold GW compact binary merger candidate
  92. Fermi trigger No 599954133: Global MASTER-Net observations report
  93. Fermi trigger No 599761015: Global MASTER-Net observations report
  94. Fermi-LAT Gamma-ray Observations of IceCube-191231A
  95. IceCube Alert 200101.46: Global MASTER-Net observations report
  96. Fermi trigger No 599603971: Global MASTER-Net observations report
  97. IceCube-191231A: Upper limits from Fermi-GBM Observations
  98. IceCube Alert 191231.46: Global MASTER-Net observations report
  99. GRB 191221B: CALET Gamma-Ray Burst Monitor detection
  100. GRB 191228A: Swift/UVOT Upper Limits

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