NICER Science Results

NICER Publications and Other Notable Items

Recent Science from NICER on the ISS

Coordinated Blazar

BL Lacertae (BL Lac) is a blazar approximately 900 million light-years from Earth. A blazar is a type of Active Galactic Nucleus (AGN), a supermassive black hole found near the center of a galaxy, viewed from the Earth nearly along the axis of one of the black hole's relativisitic jets. Blazars exhibit extremely rapid variations in flux as measured from our perspective.

On October 10th, 2020, NICER received a Target of Opportunity (TOO) request to observe BL Lac in coordination with NASA's NuSTAR (hard X-ray) and Fermi (gamma-ray) observatories. NICER regularly receives TOO requests through its publicly available online form; the Fermi Observatory had recently observed a historically high gamma-ray intensity from BL Lac, which triggered this TOO request.

NICER observed BL Lac for nearly 15 ksec on October 11-12, 2020 (see figure). The TOO requester, Dr. F. D'Ammando, is analyzing the NICER and NuSTAR data jointly to characterize the "inverse Compton peak" in the X-ray spectrum. This will provide insight into the environment of the relativistic jet in BL Lac. Initial results were reported by F. D'Ammando in Astronomer's Telegram #14096.

The measured NICER light curve of BL Lac showing X-ray intensity from varying by roughly a factor of two over the observation.

Figure: The measured NICER light curve of BL Lac showing X-ray intensity from varying by roughly a factor of two over the observation.

Latest News

  • NICER and NuSTAR observations of the Blazar BL Lac (15 Oct 2020)
    NICER and NuSTAR obtained director's discretionary observations of the blazar BL Lac after its historical optical-to-gamma ray maximum. The NICER & NuSTAR spectrum can be fit with a broken power law, and these observations confirm the active state of the source.
  • NICER detects pulsations from a new outburst of the accreting millisecond X-ray pulsar IGR J17379-3747 (01 Oct 2020)
    New NICER observations of the re-activated accreting pulsar IGR J17379-3747 recovered the 468 Hz spin period of the pulsar and made a new measurement of the change in the orbital period.
  • X-ray flaring of the nuclear transient AT2019avd (23 Sep 2020)
    Swift and NICER observations of the galactic nuclear transient discovered by the Zwicky Transient Facility shows that the source X-ray brightness increased 1000-fold over the last 5 years and show unusual X-ray properties.
  • X-ray Brightening of AT2019wey (10 Aug 2020)
    NICER and Swift have obtained X-ray observations of AT2019wey, a new transient discovered by Spektr-RG. Both NICER and Swift show continued increasing emission through August 9 from this putative accreting binary.
  • NICER XTI CALDB Updated (27 Jul 2020)
    The NICER XTI caldb has been updated to version 20200722. This version updates the detector gain, response and effective area of the XTI.

[More NICER News]