Dr. Emmanuel Momjian
National Radio Astronomy Observatory
1003 Lopezville Rd.
P. O. Box O
Socorro, NM 87801
www.nrao.edu      www.nsf.gov    www.aui.edu

List of my Books and publications

Check out some of my pictures

The press release of our Naturalization Ceremony at the VLA

Astronomy and Astrophysics Links: (select one from the menu)

About me (briefly)

I am a scientist-astronomer at the National Radio Astronomy Observatory (NRAO). When I joined NRAO in 2007, I primarily worked on the scientific-astronomical commissioning of the Expanded Very Large Array (EVLA). The project was concluded in Fall 2012, and the array was named the Karl G. Jansky Very Large Array (VLA) to honor the founder of Radio Astronomy. The VLA is the world's dominant cm-wavelength radio telescope and most sensitive interferometer operating between 1 and 50 GHz. From 2015 to 2020 I served as the lead of the VLA/VLBA Scientific User Support group. Since 2020 I have been serving as the division head for the VLA/VLBA Science Support. Before joining NRAO in 2007, I was an astronomer at the world's largest radio-radar telescope, the 305-m (1000 ft) Arecibo Radio Telescope of the National Astronomy and Ionosphere Center (NAIC). Arecibo's 900 ton platform collapsed on Dec. 1, 2020 (video), bringing an end to a very productive scientific journey that spanned 57 years. I personally used this remarkable telescope for two decades as a single dish radio telescope and as an element in VLBI arrays. I will for sure miss it!

My research is focused on high angular resolution radio observations of extragalactic objects known as LIRGs (Luminous Infrared Galaxies) and ULIRGs (Ultra Luminous Infrared Galaxies), to study both the structure and the kinematics of the central regions in these galaxies. This research includes imaging of these galaxies in radio continuum, in HI 21 cm absorption, and in OH 18 cm megamaser emission. For this research, and in order to study the nuclear active regions of these galaxies at very high spatial resolution, I mainly use the Very Long Baseline Array (VLBA) of the NRAO. However, the radio emission from these IR galaxies is very weak. Therefore, in order to have successful observations, the Very Large Array(VLA) of the NRAO, with its twenty seven 25-meter antennas, participates in these sensitivity limited observations. In some of these observations, the giant 305-meter Arecibo radio telescope was used along with both the VLBA and the VLA.

Thanks to the enhanced observational capabilities of the VLA, I have become actively involved in magnetic field studies through Methanol masers. This work has led us to discover the Zeeman effect in three Class I methanol maser transitions: at 25, 36, and 44 GHz. Visit my publications page to check the discovery and the follow-up papers on this topic (through the NASA ADS).

I am also involved in the COSMOS HI Large Extragalactic Survey (CHILES). This is a blind HI survey to detect 21 cm neutral hydrogen emission up to a redshift of 0.45 using the new capabilities of the VLA. The observations of the survey (1000 hours) have concluded already. In 2016, and using the first 178 hours of the VLA CHILES observations we have already broken the record of the highest redshift HI 21 cm detection in emission (see the NRAO press release on this topic).

I am actively involved in VLA and sensitive VLBI imaging of the radio continuum emission from very high redshift quasars, both radio-loud and radio-quiet. These quasars are believed to be near the epoch of re-ionization, i. e., when the first stars and galaxies started to form (less than 1 billion years after the Big Bang). The current redshift record for a radio-loud quasar, which has also been detected and imaged with VLBI, is z=6.82 (see the NRAO press release on this topic). We also expanded this type of work to sub-millimeter galaxies (SMGs) at z~2-3 to study and determine their nuclear power sources (AGN vs. starburst).


If you are interested in history, then you should read about the history of my people, the Armenian people, a real but painful example of a nation's survival for thousands of years (3500 years!). Here are some links:

The Armenian Genocide: The first genocide of the 20th century. During the Genocide, 1.5 million armenians perished in the turkish occupied Western Armenia. To read more, visit the Armenian National Institute

You can also read about the armenian genocide at the following web sites:
Genocide 1915
Wikipedia on Armenian Genocide
ArmenianHouse.org: an electronic library featuring a huge collection of documents on Armenian literature, history, religion and anything else Armenia-related

You can reach me by sending an email to emomjian (append @nrao.edu)

Last updated: Monday, 30-May-2022 12:49:28 MDT