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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"

8520 results found.

  1. IceCube-200117A: One Additional Candidate Counterpart from the Zwicky Transient Facility
  2. IceCube-200117A: Candidate Counterpart from the Zwicky Transient Facility
  3. IceCube-200117A: Upper limits from a search for additional neutrino events in IceCube
  4. IceCube-200117A: No Neutrino Counterpart in ANTARES data
  5. LIGO/Virgo S200115j: Updated Sky Localization and source properties
  6. LIGO/Virgo S200114f: More candidates from the Zwicky Transient Facility
  7. IceCube-200117A: Upper limits from Fermi-GBM Observations
  8. IceCube-200117A: IceCube observation of a high-energy neutrino candidate event
  9. LIGO/Virgo S200115j: Upper limits from CALET observations.
  10. LIGO/Virgo S200114f: ZTF Forced Photometry of the Swift Source S200114f_X2
  11. LIGO/Virgo S200115j: No notable candidates in GOTO imaging
  12. LIGO/Virgo S200114f: Possible X-ray transient
  13. GRB 200115A: Mondy optical afterglow candidate
  14. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  15. LIGO/Virgo S200116ah: Retraction of GW compact binary merger candidate
  16. LIGO/Virgo S200115j High Rank XRT sources are spurious
  17. LIGO/Virgo S200115j: Upper limits from Fermi-GBM Observations
  18. LIGO/Virgo S200115j: upper limits from AGILE/GRID observations
  19. LIGO/Virgo S200115j : no neutrino counterpart candidate in ANTARES search
  20. LIGO/Virgo S200114f: Upper limits from CALET observations.
  21. LIGO/Virgo S200115j: Identification of a GW compact binary merger candidate
  22. LIGO/Virgo S200115j: No counterpart candidates in HAWC observations
  23. LIGO/Virgo S200115j: Upper limits from IceCube neutrino searches
  24. LIGO/Virgo S200114f: Constraints on a CCSN origin from KM3NeT MeV neutrino search.
  25. LIGO/Virgo S200114f: SAGUARO previous detection of ZTF candidate ZTF20aafeaqk (AT2020vx)
  26. LIGO/Virgo S200114f: upper limits from AGILE-GRID observations
  27. IceCube-200109A: Candidate Counterparts from the Zwicky Transient Facility
  28. LIGO/Virgo S200114f : no neutrino counterpart candidate in ANTARES search
  29. LIGO/Virgo S200114f: Upper limits from Fermi-GBM Observations
  30. LIGO/Virgo S200114f: Identification of a GW unmodeled transient candidate
  31. LIGO/Virgo S200114f: No counterpart candidates in HAWC observations
  32. LIGO/Virgo S200114f: Upper limits from IceCube neutrino searches
  33. LIGO/Virgo S200112r: upper limits from AGILE/GRID observations
  34. LIGO/Virgo S200112r: No counterpart candidates in HAWC observations
  35. LIGO/Virgo S200112r : no neutrino counterpart candidate in ANTARES search
  36. LIGO/Virgo S200112r: Upper limits from IceCube neutrino searches
  37. LIGO/Virgo S200112r: Identification of a GW compact binary merger candidate
  38. IceCube 200109A: No significant detection in HAWC
  39. IceCube-200109A: Upper limits from a search for additional neutrino events in IceCube
  40. IceCube-200107A: Upper limits from a search for additional neutrino events in IceCube
  41. IceCube-200109A: Swift-XRT and UVoT Follow-up Observations
  42. IceCube-200109A: Upper limits from Fermi-GBM Observations
  43. IceCube-200109A: IceCube observation of a high-energy neutrino candidate event
  44. LIGO/Virgo S200105ae: Updated Sky Localization and EM-Bright Probabilities
  45. LIGO/Virgo S200105ae: Gaia Photometric Alerts transient candidate
  46. GRB 200109A: Swift detection of a burst
  47. Fermi-LAT ANTARES coincidence: Upper limits from Fermi-GBM Observations
  48. LIGO/Virgo S200105ae: GW data still under study
  49. Fermi-LAT Gamma-ray Observations of IceCube-200107A
  50. IceCube-200107A: No significant detection in HAWC
  51. LIGO/Virgo S200108v: Retraction of GW compact binary merger candidate
  52. GRB 200107B: Swift detection of a burst
  53. LIGO/Virgo S200105ae: Further study ongoing for GW compact binary merger candidate
  54. IceCube-200107A: Upper limits from Fermi-GBM Observations
  55. IceCube-200107A: IceCube observation of a high-energy neutrino candidate event
  56. LIGO/Virgo S200105ae: AstroSat CZTI upper limits
  57. LIGO/Virgo S200105ae: No counterpart candidates in HAWC observations
  58. LIGO/Virgo S200105ae: Upper limits from IceCube neutrino searches
  59. LIGO/Virgo S200105ae: Upper limits from Fermi-GBM Observations
  60. LIGO/Virgo S200105ae : no neutrino counterpart candidate in ANTARES search
  61. LIGO/Virgo S200105ae: We have issued GCN Notices to support automated processing
  62. LIGO/Virgo S200105ae: A subthreshold GW compact binary merger candidate
  63. IceCube-191231A: Upper limits from a search for additional neutrino events in IceCube
  64. IceCube-191231A: No significant detection in HAWC
  65. IceCube-191231A: No Neutrino Counterpart in ANTARES data
  66. IceCube-191231A: Upper limits from Fermi-GBM Observations
  67. IceCube-191231A: IceCube observation of a high-energy neutrino candidate event
  68. LIGO/Virgo S191216ap: Two candidate counterparts from UKIRT/WFCAM z-band observations
  69. GRB 191228A: Swift detection of a burst
  70. LIGO/Virgo S191225aq: Retraction of GW compact binary merger candidate
  71. LIGO/Virgo S191213g: Pan-STARRS monitoring shows PS19hgw (AT2019wxt) to be fading quickly
  72. LIGO/Virgo S191222n: Updated Sky Localization
  73. LIGO/Virgo S191222n: no counterpart candidate in SVOM/GWAC observations
  74. LIGO/Virgo S191216ap: Updated Source Classification
  75. LIGO/Virgo S191216ap: Upper limits from Insight-HXMT/HE observations
  76. LIGO/Virgo S191216ap: No significant candidates found in Pan-STARRS observations
  77. GRB 191221B: Zadko observatory - Gingin optical observations
  78. LIGO/Virgo S191222n : no neutrino counterpart candidate in ANTARES search
  79. LIGO/Virgo S191222n: upper limits from AGILE-GRID observations
  80. LIGO/Virgo S191222n: No counterpart candidates in HAWC observations
  81. LIGO/Virgo S191222n: Identification of a GW compact binary merger candidate
  82. LIGO/Virgo S191222n: Upper limits from IceCube neutrino searches
  83. GRB 191221B: Swift detection of a burst and a very bright optical candidate
  84. LIGO/Virgo S191216ap: No radio candidates so far in the VLA/JAGWAR galaxy targeted search
  85. GRB 191220A: AbAO optical observations
  86. LIGO/Virgo S191215w: Updated Sky Localization
  87. GRB 191220A: Swift detection of a burst
  88. LIGO/Virgo S191220af: Retraction of GW compact binary merger candidate
  89. LIGO/Virgo S191216ap: Subaru/Hyper Suprime-Cam observations of GW+IceCube+HAWC error region
  90. LIGO/Virgo S191216ap: UPDATED list of galaxies coincident with LIGO/Virgo LALInference skymap and HAWC positions
  91. LIGO/Virgo S191216ap: Updated Sky Localization
  92. LIGO/Virgo S191213g: Lulin Follow-up Observations of AT2019wxt
  93. LIGO/Virgo S191213g: Swift UVOT/XRT observations of Pan-STARRS1 candidate: PS19hgw
  94. LIGO/Virgo S191216ap: No candidates found in J-GEM follow-up observations of HAWC error region
  95. LIGO/VIRGO S191213g: ePESSTO+ spectroscopy of AT2019wxt (PS19hgw)
  96. LIGO/Virgo S191213g: HCT spectroscopy of PS19hgw / AT2019wxt
  97. LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
  98. LIGO/Virgo S191216ap: No candidates found in CHES observations of HAWC error region
  99. LIGO/Virgo S191216ap and IceCube neutrino: no counterpart candidates from AGILE-GRID observations
  100. LIGO/Virgo S191216ap: GRAWITA Loiano observations of HAWC error region

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