PhD Research

Radio signals of astronomical objects

Download my full CV here!

I have studied many different types of radio transients, which are sources that change over time in the sky.  Most recently, much of my postdoctoral research has been focused on Tidal Disruption Events (TDEs), where a star wanders too close to a black hole and gets ripped apart by tidal forces.  We can see TDEs billions of light years away, and learn both about how this process unfolds but also the environments they occur in, from the velocity of the subsequent blast wave to the density of the galactic dust it’s expanding outwards into!  To do this research I use several radio telescopes, primarily the VLA, but I have also used ALMA and MeerKAT in South Africa.  I have also used the Chandra X-ray Observatory in my quest to understand more about TDEs!

Another object I am interested in are supernovae (SNe), which are among the most titanic explosions we know of in astronomy and play a key role infuture star formation in their surrounding environments. The first few years, when the supernova is brightest in optical and other wavelengths, is well studied, but intermediate aged supernovae (~10-100 years post explosion), are far less understood despite providing the transition to a supernova remnant (SnR). Luckily, radio wavelengths can fill this gap: as the shockwave expands into the surrounding circumstellar material (CSM) ejected by the star in the tens of thousands of years prior to the explosion, electrons spiraling in magnetic fields create synchrotron emission visible in radio. In fact, this emission can be brighter in radio wavelengths in the decades after the radio emission than it was during the supernova explosion, which can provide a trove of information on how the shockwave is interacting with its surroundings as it expands, and information about the progenitor star that ejected the CSM material.

My PhD has focused on studying these intermediate aged SNe as part of a broader interest in transient and variable radio sources. I have published on the most recent observations from Supernova 1987A (SN 1987A) using the Australia Telescope Compact Array (ATCA), which has shown the re-acceleration of the shockwave in that system after interacting with dense CSM. I have also led a study on nearby Type Ia SNe 1972E and 1895B going through three decades of archival VLA observations in order to rule out models of the progenitors of these objects. Finally, I have also investigated effects of short radio transients on a technical level, focusing on finding these signals and effects of Radio Frequency Interference (RFI).

Refereed Publications

ADS Search

Refereed Publications

First Author:

1. Radio Monitoring of the Tidal Disruption Event Swift J164449.3+573451. IV. Continued Fading and Non-Relativistic Expansion. Cendes et al. 2021, ApJ, in press. [arxiv:2011.00074]
2. Thirty Years of Radio Observations of Type Ia SN 1972E and SN 1895B: Constraints on Circumstellar Shells. Cendes et al. 2020, ApJ, 894, 39. [arxiv:2001.03558]
3. The Re-Acceleration of the Shockwave in the Radio Remnant of SN 1987A. Cendes et al. 2018, ApJ, 867, 65. [arxiv: 1809.02364]
4. RFI flagging implications for short-duration transients. Cendes, Y. et al. 2018, Astronomy and Computing, 23, p. 103-114. [arxiv: 1804:04708]

Coauthor:

5. Identifying transient and variable sources in radio images. Rowlinson, A. & 18 others including Cendes. submitted to Astronomy and Computing. [1808.07781]
6. New methods to constrain the radio transient rate: results from a survey of four fields with LOFAR.
   Carbone, D. & 25 authors including Cendes, Y. N. 2016, MNRAS, 459, Issue 3, p. 1361-3174 [arxiv: 1411:7928]
7. Low-radio-frequency eclipses of the redback pulsar J2215+5135 observed in the image plane with LOFAR. Broderick, J. W. & 33 coauthors including Cendes, Y. 2016, MNRAS, 459, 3, p. 2681-2689 [arxiv: 1604:05722]
8. LOFAR MSSS: Detection of a low-frequency radio transient in 400 hrs of monitoring of the North Celestial Pole.
   Stewart, A.J. & 102 coauthors including Cendes. 2016, MNRAS, 456, 3, p. 2321-2343 [arxiv: 1512:00014]
9. The LOFAR Multifrequency Snapshot Sky Survey (MSSS) I. Survey description and first results.
   H. Heald & 140 authors including Y. Cendes. 2015, A&A, 582, id.A123. [arxiv: 1509.01257]
10. The LOFAR Transients Pipeline.
    Swinbank, John D. & 27 authors including Cendes, Yvette. 2015, Astronomy and Computing, 11, p. 25-48 [arxiv: 1503.01526]

Other Publications

Proceedings:

11. Astronomy on Reddit: Outreach Using the Front Page of the Internet. Cendes, Yvette N. 2018, Proceedings of the International Conference CAP2018, 327.

Telegrams:

12. Supernova 2015Q in NGC 3888 = Psn J11473508+5558147, Central Bureau Electronic Telegrams, 4128, 1 (2015).
    Wiggins, P. & 49 authors including Cendes, Y.
13. ASASSN-15lu is a Type Ia Supernova, The Astronomer’s Telegram, #7707 (2015)
    Leonard, D. C. &47 others including Cendes, Y.
14. Optical Spectroscopy of PSN J15044078+1237436, The Astronomer’s Telegram, #7690 (2015)
    Leonard, D. C. &47 others including Cendes, Y.
15. PSN J11473508+5558147 is a Type Ib Supernova Near Maximum Light, The Astronomer’s Telegram, #7680 (2015)
    Leonard, D. C. &47 others including Cendes, Y.
16. ASASSN-15lo is a Post-Maximum Normal Type Ia Supernova, The Astronomer’s Telegram, #7675
    Leonard, D. C. &47 others including Cendes, Y.

PhD Research

Radio signals of astronomical objects

Supernovae (SNe) are among the most titanic explosions we know of in astronomy, and they play a key role infuture star formation in their surrounding environments. The first few years, when the supernova is brightest in optical and other wavelengths, is well studied, but intermediate aged supernovae ($\sim$10-100 years post explosion), are far less understood despite providing the transition to a supernova remnant (SnR). Luckily, radio wavelengths can fill this gap: as the shockwave expands into the surrounding circumstellar material (CSM) ejected by the star in the tens of thousands of years prior to the explosion, electrons spiraling in magnetic fields create synchrotron emission visible in radio. In fact, this emission can be brighter in radio wavelengths in the decades after the radio emission than it was during the supernova explosion, which can provide a trove of information on how the shockwave is interacting with its surroundings as it expands, and information about the progenitor star that ejected the CSM material.

My PhD has focused on studying these intermediate aged SNe as part of a broader interest in transient and variable radio sources. I have published on the most recent observations from Supernova 1987A (SN 1987A) using the Australia Telescope Compact Array (ATCA), which has shown the re-acceleration of the shockwave in that system after interacting with dense CSM. I have also led a study on nearby Type Ia SNe 1972E and 1895B going through three decades of archival VLA observations in order to rule out models of the progenitors of these objects. Finally, I have also investigated effects of short radio transients on a technical level, focusing on finding these signals and effects of Radio Frequency Interference (RFI).

Download my full CV here!

Refereed Publications

ADS Search

First Author:

1. The Re-Acceleration of the Shockwave in the Radio Remnant of SN 1987A. 2018, Cendes et al. ApJ, in press. [arxiv: 1809.02364]
2. RFI flagging implications for short-duration transients. Cendes, Y. et al. 2018, Astronomy and Computing, 23, p. 103-114. [arxiv: 1804:04708]
3. Radio Constraints on the Progenitors and Evolution of Type Ia SN 1972E and SN 1895B. Cendes et al. 2018, in prep.

Coauthor:

4. Identifying transient and variable sources in radio images. Rowlinson, A. & 18 others including Cendes. submitted to Astronomy and Computing. [1808.07781]
5. New methods to constrain the radio transient rate: results from a survey of four fields with LOFAR.
   Carbone, D. & 25 authors including Cendes, Y. N. 2016, MNRAS, 459, Issue 3, p. 1361-3174 [arxiv: 1411:7928]
6. Low-radio-frequency eclipses of the redback pulsar J2215+5135 observed in the image plane with LOFAR. Broderick, J. W. & 33 coauthors including Cendes, Y. 2016, MNRAS, 459, 3, p. 2681-2689 [arxiv: 1604:05722]
7. LOFAR MSSS: Detection of a low-frequency radio transient in 400 hrs of monitoring of the North Celestial Pole.
   Stewart, A.J. & 102 coauthors including Cendes. 2016, MNRAS, 456, 3, p. 2321-2343 [arxiv: 1512:00014]
8. The LOFAR Multifrequency Snapshot Sky Survey (MSSS) I. Survey description and first results.
   H. Heald & 140 authors including Y. Cendes. 2015, A&A, 582, id.A123. [arxiv: 1509.01257]
9. The LOFAR Transients Pipeline.
   Swinbank, John D. & 27 authors including Cendes, Yvette. 2015, Astronomy and Computing, 11, p. 25-48 [arxiv: 1503.01526]

Other Publications

Proceedings:

10. Astronomy on Reddit: Outreach Using the Front Page of the Internet. Cendes, Yvette N. 2018, IAU Communicating Astronomy with the Public Conference.

Telegrams:

11. Supernova 2015Q in NGC 3888 = Psn J11473508+5558147, Central Bureau Electronic Telegrams, 4128, 1 (2015).
    Wiggins, P. & 49 authors including Cendes, Y.
12. ASASSN-15lu is a Type Ia Supernova, The Astronomer’s Telegram, #7707 (2015)
    Leonard, D. C. &47 others including Cendes, Y.
13. Optical Spectroscopy of PSN J15044078+1237436, The Astronomer’s Telegram, #7690 (2015)
    Leonard, D. C. &47 others including Cendes, Y.
14. PSN J11473508+5558147 is a Type Ib Supernova Near Maximum Light, The Astronomer’s Telegram, #7680 (2015)
    Leonard, D. C. &47 others including Cendes, Y.

• ASASSN-15lo is a Post-Maximum Normal Type Ia Supernova, The Astronomer’s Telegram, #7675
  Leonard, D. C. &47 others including Cendes, Y.