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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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submitter:"Judith Racusin"

7455 results found.

  1. LIGO/Virgo S190910h: No counterpart candidates in HAWC observations
  2. LIGO/Virgo S190910h: Upper limits from Fermi-GBM Observations
  3. LIGO/Virgo S190910h : no neutrino counterpart candidate in ANTARES search
  4. LIGO/Virgo S190910h: Upper limits from IceCube neutrino searches
  5. LIGO/Virgo S190910h: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo S190910d: Candidates from the Zwicky Transient Facility
  7. LIGO/Virgo S190910d: no counterpart candidates in AGILE-GRID observations
  8. LIGO/Virgo S190910d : no neutrino counterpart candidate in ANTARES search
  9. LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
  10. ZTF19abvizsw: No counterpart candidates from Swift/BAT targeted search
  11. LIGO/Virgo S190910d: No counterpart candidates in HAWC observations
  12. LIGO/Virgo S190910d: Identification of a GW compact binary merger candidate
  13. LIGO/Virgo S190910d: Upper limits from IceCube neutrino searches
  14. ZTF19abvizsw/AT2019pim, search for GRB in SPI-ACS/INTEGRAL data
  15. LIGO/Virgo S190901ap: ZTF19abwvals is a type-Ia SN near maximum
  16. LIGO/Virgo S190901ap: Second Epoch Hobby-Eberly Telescope observations of ZTF19abvionh
  17. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  18. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate MASTER OT J171434.95+280725.6
  19. LIGO/Virgo S190901ap: Dabancheng-0.5m optical observations of AT2019pjv
  20. LIGO/Virgo S190901ap: Additional candidates from the Zwicky Transient Facility
  21. LIGO/Virgo S190901ap: GOTO optical coverage and detection of AT2019pjv
  22. LIGO/Virgo S190901ap : GRAWITA photometric observation of candidate ZTFabvizsw and GCN 25618 revision
  23. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  24. Liverpool Telescope observations of ZTF19abvizsw, a candidate untriggered GRB afterglow
  25. LIGO/Virgo S190901ap: Additional observations from the Zwicky Transient Facility
  26. LIGO/Virgo S190901ap: GROWTH-India follow-up of ZTF19abvionh
  27. Chandra observations of GW170817 ~740-743 days since merger
  28. LIGO/Virgo S190901ap: Upper limits from AGILE-GRID observations
  29. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  30. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  31. LIGO/Virgo S190901ap: No neutrino candidates at Pierre Auger Observatory
  32. LIGO/Virgo S190901ap: Hobby-Eberly Telescope VIRUS observations of ZTF19abvionh
  33. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate ZTFabvixoy
  34. LIGO/Virgo S190901ap : GRAWITA spectroscopic observation of candidate ZTFabvizsw
  35. LIGO/Virgo S190901ap: Candidates from the Zwicky Transient Facility
  36. LIGO/Virgo S190901ap: Updated Sky Localization
  37. LIGO/Virgo S190901ap : no neutrino counterpart candidate in ANTARES search
  38. LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
  39. LIGO/Virgo S190901ap: No counterpart candidates in HAWC observations
  40. LIGO/Virgo S190901ap: Identification of a GW compact binary merger candidate
  41. LIGO/Virgo S190901ap: Upper limits from IceCube neutrino searches
  42. LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidate AT2019ntp
  43. GRB 190829A: No Neutrino Counterpart detected with ANTARES
  44. LIGO/Virgo S190814bv: Upper limits from a two-week IceCube search for neutrinos from the direction of ASKAP J005547-270433
  45. LIGO/Virgo S190829u: Retraction of GW compact binary merger candidate
  46. GRB 190829A: Swift detection of a burst consistent with a galaxy at z=0.08
  47. GRB 190828B: VLT/X-shooter optical afterglow candidate
  48. LIGO/Virgo S190426c: Update on Probability of Terrestrial Origin
  49. LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidates AT2019ntr and AT2019omx
  50. LIGO/Virgo S190814bv: VLA observation of ASKAP J005547-270433/AT2019osy
  51. GRB 190828A: Tiled Swift observations
  52. LIGO/Virgo S190814bv: Swift UVOT - no new counterpart candidates identified
  53. LIGO/Virgo S190828l: Upper limits from Fermi-GBM Observations
  54. LIGO/Virgo S190828j: Upper limits from Fermi-GBM Observations
  55. GRB 190828B: Swift detection of a burst
  56. LIGO/Virgo S190828l: Upper limits from AGILE-GRID observations
  57. LIGO/Virgo S190828l: Upper limits from IceCube neutrino searches
  58. LIGO/Virgo S190828j: Upper limits from IceCube neutrino searches
  59. LIGO/Virgo S190828j : no neutrino counterpart candidate in ANTARES search
  60. LIGO/Virgo S190828l : no neutrino counterpart candidate in ANTARES search
  61. LIGO/Virgo S190828j: Upper limits from AGILE-GRID observations
  62. LIGO/Virgo S190828j: Updated Sky Localization
  63. LIGO/Virgo S190828l: Identification of a GW compact binary merger candidate
  64. LIGO/Virgo S190828l: No counterpart candidates in HAWC observations
  65. LIGO/Virgo S190828j: No counterpart candidates in HAWC observations
  66. LIGO/Virgo S190828j: Identification of a GW compact binary merger candidate
  67. LIGO/Virgo S190814bv: Correction of ASKAP coordinates
  68. LIGO/Virgo S190814bv: DESGW non-detection of AT2019osy/ASKAP 005547-270433
  69. LIGO/Virgo S190814bv: Optical non-detection of radio source AT2019osy from CFHT
  70. Fermi GBM-190816: Eight additional candidates from the Zwicky Transient Facility
  71. LIGO/Virgo S190814bv: Detection of a candidate radio counterpart with ASKAP
  72. LIGO/Virgo S190814bv: Final list of candidates from the DESGW coadd analysis from the week long search campaign
  73. LIGO/Virgo S190814bv: CFHTphotometryof AT2019npv
  74. LIGO/Virgo S190814bv: SOAR spectroscopy of DECam candidates AT2019npw and AT2019num
  75. LIGO/Virgo S190814bv: SALT optical spectrum of candidate DG19aqbkc
  76. LIGO/Virgo S190814bv: MASTER prediscovery and postdiscovery observations DECam candidate DG19wxnjc/AT2019npv field
  77. Fermi GBM-190816: Updated localization of subthreshold GRB-GW candidate
  78. GRB 190824A: Swift detection of a burst
  79. LIGO/Virgo S190814bv: Keck NIRES spectroscopy of DG19wxnjc/AT2019npv
  80. GRB 190823A: Tiled Swift observations
  81. LIGO/Virgo S190814bv: DESGW photometry of AT2019npv
  82. LIGO/Virgo S190814bv: GROND follow-up observations of AT2019npv
  83. LIGO/Virgo S190814bv: ENGRAVE VLT/HAWK-I observations and archival detection of the CFHT candidate
  84. LIGO/Virgo S190814bv: No radio counterpart detected in ASKAP observations
  85. LIGO/Virgo S190814bv: a potential faint optical counterpart in CFHT imaging
  86. LIGO/Virgo S190822c: Retraction of GW compact binary merger candidate
  87. LIGO/Virgo S190822c: CLU/NED Galaxies in the 50% Localization Volume
  88. LIGO/Virgo S190822c: Upper limits from IceCube neutrino searches
  89. LIGO/Virgo S190814bv: new candidate from DESGW
  90. GRB 190821A: MASTER do not see any afterglow candidate
  91. Fermi GBM-190816: Four additional candidates from the Zwicky Transient Facility
  92. GRB 190821A: Swift detection of a burst
  93. LIGO/Virgo S190814bv: further candidates from DESGW
  94. Fermi GBM-190816: AGILE in SAA at T0
  95. LIGO/Virgo S190814bv: SOAR spectroscopy of AT2019noq and AT2019ntn
  96. Fermi GBM-190816: One candidate counterpart from the Zwicky Transient Facility
  97. LIGO/Virgo S190814bv: Further Pan-STARRS observations and transient sources
  98. Fermi GBM-190816: Upper limits from IceCube neutrino searches
  99. Fermi GBM-190816: No counterpart candidates in HAWC observations
  100. LIGO/Virgo S190814bv: No neutrino candidates at Pierre Auger Observatory

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