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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.

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200 results found.

  1. LIGO/Virgo G298048: TOROS optical counterpart search (continuation)
  2. LIGO/Virgo G298048: TOROS optical counterpart search
  3. LIGO/Virgo G298048: optical observations of CHILESCOPE observatory
  4. LIGO/Virgo G298048: Pan-STARRS izy photometry monitoring of SSS17a/DLT17ck
  5. LIGO/Virgo G298048: VLA observation at 6 GHz
  6. LIGO/Virgo G298048: Continued VLA observations
  7. LIGO/Virgo G298048: Possible X-ray detection with Swift
  8. LIGO/VIRGO G298048: SALT optical spectra of the candidate optical/NIR counterpart of the gravitational wave G298048 in NGC4993.
  9. LIGO/Virgo G298048: Etelman Observatory observation of the potential LIGO EM counterpart SSS17a
  10. LIGO/Virgo G298048: GROND observations of candidate optical counterpart
  11. LIGO/Virgo G298048: Continued observation for DLT17ck
  12. LIGO/Virgo G298048: GMRT Follow-up of SSS17a
  13. LIGO/Virgo G298048: La Silla - QUEST archival non-detections of of LIGO EM counterpart SSS17a
  14. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations
  15. LIGO/Virgo G298048: KMTNet and other optical follow-up observations
  16. LIGO/Virgo G298048: further REM optical/NIR observations of candidate in NGC 4993
  17. LIGO/Virgo G298048: Subaru HSC z-band photometry confirms the fading nature of SSS17a
  18. LIGO/Virgo G298048: VLT linear polarimetry
  19. LIGO/Virgo G298048: GRAWITA VLT/X-shooter observations
  20. LIGO/Virgo G298048: NOT near-infrared observations of SSS17a
  21. LIGO/Virgo G298048: Further Pan-STARRS izy photometry confirms rapid fading of SSS17a/DLT17ck in i and z bands
  22. LIGO/Virgo G298048: Further VLA Observations
  23. LIGO/Virgo G298048: VLBA observations of the possible counterpart SSS17a in NGC 4993
  24. LIGO/Virgo G298048: MASTER photometry of the SSS17a in NGC 4993
  25. LIGO/Virgo G298048: HSC observations of the OT candidate of G298048
  26. LIGO/Virgo G298048: Possible features in the spectrum of GW counterpart SSS17a
  27. LIGO/Virgo G298048: GROND photometry of candidate optical counterpart reveals brightening in the NIR
  28. LIGO/Virgo G298048: Additional Swope Observations of SSS17a
  29. LIGO/VIRGO G298048: ePESSTO optical spectra of the candidate optical/NIR counterpart of the gravitational wave G298048 in NGC4993.
  30. LIGO/Virgo G298048: Rapid Evolution of Possible Counterpart
  31. LIGO/Virgo G298048: Observed fading of optical counterpart SSS17a
  32. LIGO/Virgo G298048: Continued observation for DLT17ck
  33. LIGO/VIRGO G298048: Expansion Velocity of SSS17a Consistent With Relativistic Merger Ejecta
  34. LIGO/Virgo G298048: optical spectral energy distribution of SSS17a
  35. LIGO/Virgo G298048: prior photometry from VISTA Hemisphere Survey
  36. LIGO/Virgo G298048: Archival 2MASS and Spitzer non-detections of the potential LIGO EM counterpart SSS17a
  37. LIGO/Virgo G298048: ATCA upper limits on radio emission from optical source SSS17a in NGC 4993
  38. LIGO/Virgo G298048: Continued Swift UV and X-ray Monitoring of SSS17a
  39. LIGO/Virgo G298048: Archival VLA observations
  40. LIGO/Virgo G298048: New MASTER observations of the OT in NGC 4993
  41. LIGO/Virgo G298048: Additional Gemini-South acknowledgements
  42. LIGO/Virgo G298048: UPDATE on IceCube neutrino candidates --- no coincidence with newest GW skymap
  43. LIGO/Virgo G298048: Correction to Swope photometry announced in LVC GCN 21529
  44. LIGO/Virgo G298048: Moderate dimming or no brightening of the optical counterpart candidate?
  45. LIGO/Virgo G298048: Brightening of Possible Counterpart
  46. LIGO/Virgo G298048: AGILE-GRID analysis of the potential counterpart field
  47. LIGO/Virgo G298048: Observation of the potential optical counterpart in NGC 4993
  48. LIGO/Virgo G298048: ASKAP search for fast radio bursts
  49. LIGO/Virgo G298048: Subaru HSC z-band photometry of the possible optical counterpart
  50. LIGO/Virgo G298048: SkyMapper uvgri photometry of the candidate in NGC 4933
  51. LIGO/Virgo G298048: ATCA detection of a radio source coincident with NGC 4993
  52. LIGO/Virgo G298048: TZAC TAROT Reunion (TRE) observations
  53. LIGO/Virgo G298048: Likelihood of SSS17a Being an Unrelated Extragalactic Transient in NGC 4993
  54. LIGO/Virgo G298048: REM optical/NIR observations
  55. LIGO/Virgo G298048, Fermi GBM trigger 524666471/170817.529: MAXI/GSC observations
  56. LIGO/Virgo G298048: HCT observations
  57. LIGO/Virgo G298048: Pan-STARRS detections and izy photometry of the possible optical/NIR counterpart in NGC4993
  58. LIGO/Virgo G298048: Gemini-South Near-Infrared Photometry of the Optical Transient Candidate
  59. LIGO/Virgo G298048: Magellan g-band Imaging of the Potential Optical Counterpart Associated with NGC 4993
  60. LIGO/VIRGO G298048: Swift UVOT detection and XRT upper limits
  61. LIGO/Virgo G298048: Subaru HSC follow-up observations
  62. LIGO/Virgo G298048: VLA Refined Analysis
  63. LIGO/VIRGO G298048: Magellan Optical Spectrum of the Potential Optical Counterpart Associated with NGC 4993
  64. LIGO/Virgo G298048: MASTER observations of the NGC 4993
  65. LIGO/Virgo G298048: VLA Detection
  66. LIGO/Virgo G298048: VISTA/VIRCAM detection of candidate counterpart
  67. LIGO/Virgo G298048: Galaxy-Targeted Optical Followup With Las Cumbres Observatory
  68. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival SkyMapper Transient Survey Data
  69. LIGO/VIRGO G298048: The Potential Optical Counterpart in NGC 4993 Has Afterglow-Like Colors
  70. LIGO/Virgo G298048: DLT40 follow-up observation
  71. LIGO/Virgo G298048: Las Cumbres Observatory Detection of The Possible Optical Counterpart in NGC 4993
  72. LIGO/Virgo G298048: ATCA observations of candidate host galaxies
  73. LIGO/Virgo G298048: Inspection of archival HST data at the position of the potential optical counterpart
  74. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume using the updated sky map computed using LALInference
  75. LIGO/Virgo G298048 : Fermi-LAT search for a high-energy gamma-ray counterpart
  76. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival ASAS-SN Data
  77. LIGO/Virgo G298048: REM optical/NIR observations of candidate in NGC 4993
  78. LIGO/Virgo G298048: DLT40 optical candidate
  79. LIGO/Virgo G298048: DECam optical candidate
  80. LIGO/Virgo G298048: Potential optical counterpart discovered by Swope telescope
  81. LIGO/Virgo G298048 - Update on Fermi/GBM GRB 170817A Analysis
  82. LIGO/Virgo G298048: Updated sky map from gravitational-wave data
  83. LIGO/Virgo G298048: AGILE GRID observations
  84. LIGO/Virgo G298048: AGILE MCAL observations
  85. LIGO/Virgo G298048: Swift/BAT data search
  86. LIGO/Virgo G298048 ANTARES search
  87. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume with Face-on Assumption
  88. LIGO/Virgo G298048: Nearby Galaxies in the Localization Volume
  89. LIGO/Virgo G298048: Insight-HXMT observations
  90. LIGO/Virgo G298048: Potential host galaxies from the GLADE catalog
  91. LIGO/Virgo G298048: IPN triangulation of Fermi/GBM trigger 524666471/170817529
  92. LIGO/Virgo G298048: Astrosat CZTI upper limits
  93. LIGO/Virgo G298048: Further analysis of a binary neutron star candidate with updated sky localization
  94. LIGO/Virgo G298048: COINCIDENT IceCube neutrino candidate with Fermi GBM trigger 524666471/170817529
  95. LIGO/Virgo G298048: correction to the luminosity distance reported in GCN 21509
  96. LIGO/Virgo G298048: Identification of a binary neutron star candidate coincident with Fermi GBM trigger 524666471/170817529
  97. LIGO/Virgo G298048: FOUND COINCIDENT IceCube neutrino observation
  98. LIGO/Virgo G298048: INTEGRAL detection of a prompt gamma-ray counterpart
  99. LIGO/Virgo G298048: Fermi GBM trigger 170817.529 and LIGO single IFO trigger
  100. LIGO/Virgo G298048: Fermi GBM trigger 524666471/170817529: LIGO/Virgo Identification of a possible gravitational-wave counterpart

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