November 2, 2020 – Elaina Hancock – UConn Communications The Sloan Digital Sky Survey’s fifth generation – a groundbreaking project to bolster our understanding of the formation and evolution of galaxies, including the Milky Way – collected its very first observations on the evening of October 23. Image: The Sloan Digital Sky Survey’s fifth generation […][Read More]
UConn Astrophysicist and observational astronomer Jonathan Trump was a recent guest on UConn 360, a podcast from the Storrs campus of the University of Connecticut. In this conversation, Jonathan tells about how attending a lecture as an undergraduate at Penn State captured his interest and changed the course of his professional career. Now Jonathan offers […][Read More]
Amelia Henkel, graduating Double Major in Physics and Human Rights, and President of the Undergraduate Women in Physics Club, speaks on the CLAS website about her passion for physics and human rights, and how she mastered challenges in her remarkably interdisciplinary curriculum. “We really need to interact with other disciplines,” says Amelia, “because that’s […][Read More]
The University of Connecticut’s Katherine Whitaker is part of a team of astronomers who have put together the largest and most comprehensive “history book” of the universe from 16 years’ worth of observations from NASA’s Hubble Space Telescope.This image, a mosaic of nearly 7,500 separate Hubble exposures, presents a wide portrait of the distant universe and contains roughly 265,000 galaxies that stretch back through 13.3 billion years to just 500 million years after the Big Bang.[Read More]
This image is the first ever taken of a black hole, captured by the Event Horizon Telescope (EHT) project. The black center is a direct view of the event horizon of a supermassive black hole with a mass of 6.5 billion times the Sun, lying at the center of the Virgo cluster of galaxies. The bright ring is emission from hot gas just above the event horizon, with an asymmetric shape caused by gravitational lensing of light in the strong gravity of the black hole. The EHT collaboration captured the image using a network of 8 radio telescopes that spanned the Earth.[Read More]
Original UConn Today article here Rising Star in Astrophysics Receives Sloan Foundation Fellowship February 19, 2019 – Jessica McBride – Office of the Vice President for Research Kate Whitaker, assistant professor of physics, stands next to a telescope inside the observatory on top of the Gant Complex on Feb. 14, 2019. (Peter Morenus/UConn Photo) As […][Read More]
A young Cara Battersby once scrawled out the phrase “Science is curious” in a school project about what she wanted to do when she grew up.
This simple phrase still captures Battersby’s outlook on her research about our universe.
Recently shortlisted for the 2018 Nature Research Inspiring Science Award, Battersby has been working on several projects aimed at unfolding some of the most compelling mysteries of galaxies near and far.
“I’m really interested in how stars are born,” Battersby says. “They’re the source of all life on Earth.”
Battersby is leading an international team of over 20 scientists to map the center of the Milky Way Galaxy using the Submillimeter Array in Hawaii, in a large survey called CMZoom. She was recently awarded a National Science Foundation grant to follow-up on this survey and create a 3D computer modeled map of the center of the Milky Way Galaxy.[Read More]
Physics major Brenna Robertson has been selected as the recipient of the 2018 Mark Miller Undergraduate Research Award. Brenna’s proposal, which focuses on modeling supermassive black hole spin using spectral emission diagrams, was selected from among a strong pool of applicants. Brenna Robertson is working with Prof. Jonathan Trump. The Mark Miller Award is a […][Read More]
Undergraduate Physics Majors, Sam Cutler and Anthony (Josh) Machado, recently received awards from the NASA Connecticut Space Grant Consortium. Sam was awarded an Undergraduate Research Fellowship to perform research at UConn this summer working with Prof. Kate Whitaker. The title of his research project is “Examining High Redshift Rotation Curve Outside the Local Universe”. Josh […][Read More]
An artist’s rendering of hot material falling into a supermassive black hole, creating what is called the accretion disk, shown in orange. Reverberation mapping measures the time it takes light to travel between two areas of the accretion disk. The ‘light echo’ enables direct measurement of the mass of the black hole. This reverberation mapping […][Read More]
Two UConn physics professors will be among the world’s first scientists to explore the universe using the new James Webb Space Telescope. The highly competitive, peer-reviewed James Webb Space Telescope Early Release Science program was created to test the capabilities of the new observatory and to showcase the tools the telescope is equipped with. Of more than 100 proposals submitted, only 13 were chosen to participate in the early release phase, including two separate proposals involving UConn researchers Kate Whitaker and Jonathan Trump, both assistant professors of physics.[Read More]
For the first time, scientists have directly detected gravitational waves — ripples in space-time — in addition to light from the spectacular collision of two neutron stars. This marks the first time that a cosmic event has been viewed in both gravitational waves and light. The discovery was made using the U.S.-based Laser Interferometer Gravitational-Wave […][Read More]
Dr. Siddharth Mohite, UW-Milwaukee and CCA, Flatiron Institute, "Investigating Populations across the Gravitational-Wave Mass Spectrum: Statistical Tools and Implications for Astrophysics", Astronomy Seminar11:30am
Dr. Siddharth Mohite, UW-Milwaukee and CCA, Flatiron Institute, "Investigating Populations across the Gravitational-Wave Mass Spectrum: Statistical Tools and Implications for Astrophysics", Astronomy Seminar
Wednesday, March 3rd, 2021
11:30 AM - 12:00 PM
Storrs Campus onlineDr. Siddharth Mohite, UW-Milwaukee and CCA, Flatiron Institute
Investigating Populations across the Gravitational-Wave Mass Spectrum: Statistical Tools and Implications for Astrophysics
Merging compact object binaries comprising of pairs of black holes, neutron stars or a neutron star and a black hole are energetic sources of gravitational-wave (GW) and electromagnetic (EM) radiation. Current and future gravitational-wave observatories such as LIGO-Virgo-KAGRA, LISA and NANOGrav will help uncover a diverse population of these binaries across the mass spectrum. While the LIGO-Virgo-KAGRA observatories probe compact objects roughly from 1 to 100 times a solar mass, observatories such as LISA and NANOGrav are predicted to probe supermassive binaries in the million to billion solar mass regimes. On the other hand, telescopes around the world will aid in detecting binaries that contain neutron stars by observing an associated electromagnetic counterpart called a kilonova. Investigating the properties of these binary populations will shed light on some long-standing problems in astrophysics such as stellar and galaxy evolution and nuclear equation of state. In this talk, I will present an attempt to create a Bayesian framework that can simultaneously use information from GW and EM surveys to place constraints on the kilonova population. I will also briefly introduce a method to model the mass distribution of binaries detectable by LIGO-Virgo-KAGRA, using Gaussian processes. Finally, I will also present some investigations into modeling the effects of circum-binary gas and eccentricity on the expected gravitational-wave sources from merging supermassive black hole binaries detectable by observatories like NANOGrav.
Joyce Caliendo, University of Connecticut , "Early Science with the Large Millimeter Telescope: Constraining the Gas Fraction of a Compact Quiescent Galaxy at z = 1.883 ", Astronomy Seminar11:00am
Joyce Caliendo, University of Connecticut , "Early Science with the Large Millimeter Telescope: Constraining the Gas Fraction of a Compact Quiescent Galaxy at z = 1.883 ", Astronomy Seminar
Wednesday, March 3rd, 2021
11:00 AM - 11:30 AM
Storrs Campus onlineJoyce Caliendo, University of Connecticut
Early Science with the Large Millimeter Telescope: Constraining the Gas Fraction of a Compact Quiescent Galaxy at z = 1.883
We present constraints on the dust continuum flux and inferred gas content of a gravitationally lensed massive quiescent galaxy at z=1.883 +/- 0.001 using AzTEC 1.1mm imaging with the Large Millimeter Telescope. MRG-S0851 appears to be a prototypical massive compact quiescent galaxy but has evidence that it experienced a centrally concentrated rejuvenation event in the last 100 Myr. This galaxy is undetected in the AzTEC image but we calculate an upper limit on the millimeter flux and use this to estimate the H_2 mass limit via an empirically calibrated relation that assumes a constant molecular gas-to-dust ratio of 150.
We constrain the 3 sigma upper limit of the H_2 fraction from the dust continuum in MRG-S0851 to be M_(H_2)/M_* < 6.8%. MRG-S0851 has a low gas fraction limit with a moderately low sSFR owing to the recent rejuvenation episode, which together results in a relatively short depletion time of
Dr. S. Feeney, UCL, "Clarifying the Hubble Constant Tension", Astronomy Seminar11:00am
Wednesday, February 24th, 2021
11:00 AM - 12:00 PM
Storrs Campus onlineDr. S. Feeney, UCL
Clarifying the Hubble Constant Tension
Our best estimate of the Universe's current expansion rate (the Hubble constant) from the local Universe (via the Cepheid distance ladder) is in four-sigma tension with the value extrapolated from cosmic microwave background data assuming the standard cosmology. Whether this discrepancy represents physics beyond the Standard Model or deficiencies in our understanding of the data is the subject of intense debate. In this talk, I will review the community's attempts to explain and interpret the Hubble constant tension, clarifying the current picture using Bayesian probability theory, and consider the potential for independent gravitational wave observations to arbitrate the dispute.
Contact Information: Prof. C. MingarelliMore
Dr. Kris Pardo, Jet Propulsion Laboratory , "Detecting Gravitational Waves and Dark Matter with the Roman Space Telescope's Exoplanet Microlensing Survey", Astronomy Seminar11:00am
Dr. Kris Pardo, Jet Propulsion Laboratory , "Detecting Gravitational Waves and Dark Matter with the Roman Space Telescope's Exoplanet Microlensing Survey", Astronomy Seminar
Wednesday, February 10th, 2021
11:00 AM - 12:00 PM
Storrs Campus onlineDr. Kris Pardo, Jet Propulsion Laboratory
Detecting Gravitational Waves and Dark Matter with the Roman Space Telescope's Exoplanet Microlensing Survey
The Roman Space Telescope's Exoplanet Microlensing Survey will take tens of thousands of exposures of 10 million stars over 5 years, pinpointing their positions with extreme accuracy. The nominal purpose of this mission is to detect over a thousand planets; however, its unique design and excellent astrometric precision also open other avenues of astrophysical study. Gravitational waves and dark matter halos can both cause apparent changes in stellar positions in a correlated manner. In this talk, I will explain these phenomena and how this survey will let us study supermassive black hole populations and dark matter properties.
WebEx meeting URL: https://uconn-cmr.webex.com/meet/cmf19005
Contact Information: Prof. C. FaesiMore
Dr. A. Stevens, NSF Postdoctoral Fellow, Michigan State University and University of Michigan, "Mapping Matter in Strong Gravity: Spectral-Timing of Black Holes and Neutron Stars ", Astronomy Seminar11:00am
Dr. A. Stevens, NSF Postdoctoral Fellow, Michigan State University and University of Michigan, "Mapping Matter in Strong Gravity: Spectral-Timing of Black Holes and Neutron Stars ", Astronomy Seminar
Wednesday, February 3rd, 2021
11:00 AM - 12:00 PM
Storrs Campus onlineDr. A. Stevens, NSF Postdoctoral Fellow, Michigan State University and University of Michigan
Mapping Matter in Strong Gravity: Spectral-Timing of Black Holes and Neutron Stars
One of the best laboratories to study strong-field gravity is the inner 100s of kilometers around black holes and neutron stars in binary systems with low-mass stars like our Sun. The X-ray light curves of these systems show variability on timescales from milliseconds to months -- the rapid variability can appear as quasi-periodic oscillations (QPOs), which may be produced by general relativistic effects. My research looks at QPOs from black holes and neutron stars by applying state-of-the-art "spectral-timing" techniques to constrain the physical origin of these signals. In this talk, I will discuss data from NICER, an X-ray telescope attached to the International Space Station. I will also highlight open-source astronomy research software and the importance of mental wellbeing in academia.
Webex link: https://uconn-cmr.webex.com/meet/jot16106
Contact Information: Prof. J. TrumpMore
Prof. P. Mannheim, Department of Physics, University of Connecticut, "Is Dark Matter Fact or Fantasy -- Clues from the Data", Astronomy Seminar11:00am
Prof. P. Mannheim, Department of Physics, University of Connecticut, "Is Dark Matter Fact or Fantasy -- Clues from the Data", Astronomy Seminar
Wednesday, January 27th, 2021
11:00 AM - 12:00 PM
Storrs Campus onlineProf. P. Mannheim,
Department of Physics, University of Connecticut
Is Dark Matter Fact or Fantasy -- Clues from the Data
We discuss arguments both in favor of and against dark matter. With the repeated failure of experiment to date to detect dark matter we discuss what could be done instead, and to this end look for clues in the data themselves. We identify various regularities in galactic rotation curve data that correlate the total gravitational potential with luminous matter rather than dark matter. We identify a contribution to galactic rotation curves coming from the rest of the visible universe, and suggest that dark matter is just an attempt to describe this global effect in terms of standard local Newtonian gravity within galaxies. Thus the missing mass is not missing at all -- it has been hiding in plain sight all along as the rest of the visible mass in the universe.
Webex link: https://uconn-cmr.webex.com/meet/cab16109
Dr. Caitlin Witt, Department of Physics and Astronomy, West Virginia University, Astronomy Seminar10:00am
Wednesday, January 20th, 2021
10:00 AM - 11:00 AM
Storrs Campus onlineDr. Caitlin Witt, Department of Physics and Astronomy, West Virginia University
Multimessenger Astrophysics in the NANOGrav Pulsar Timing Array
Nearly all galaxies contain supermassive black holes, and when these galaxies merge, they can form supermassive black hole binaries. As they progress towards merger, these binaries emit strong nanohertz gravitational waves (GWs). In the next few years, pulsar timing arrays will reach the sensitivities required to detect GWs from both individual supermassive black hole binaries, as well as the stochastic GW background formed by the entire population of these binaries. However, GWs are not the only method used to search for supermassive binaries; by combining GW searches with electromagnetic searches, we enter the regime of multimessenger astrophysics. In this talk, I'll discuss multimessenger efforts within the NANOGrav pulsar timing array, including the recently published targeted multimessenger search for GWs that I led for the collaboration. We developed the first collaboration toolkit for analysis of multimessenger data, and applied it to the well-known binary candidate 3C 66B. We also demonstrated improvements to constraints that can be made by including electromagnetic data in this way. I'll also present some of my ongoing work on the electromagnetic searches for supermassive black hole binaries, where we are exploring the capabilities of binary detection methods on AGN with periodic variability, for both existing and future time-domain surveys.
Webex link: https://uconn-cmr.webex.com/meet/cmf19005
Contact Information: Dr. A. HuangMore
Anahita Alavi, University of California, Riverside, "Dwarf Galaxies Before Exciting Future Observations: The Importance of Extragalactic HST UV Imaging Surveys", Astronomy Seminar12:00pm
Anahita Alavi, University of California, Riverside, "Dwarf Galaxies Before Exciting Future Observations: The Importance of Extragalactic HST UV Imaging Surveys", Astronomy Seminar
Wednesday, December 9th, 2020
12:00 PM - 01:00 PM
Storrs Campus onlineAnahita Alavi, University of California, Riverside
Dwarf Galaxies Before Exciting Future Observations: The Importance of Extragalactic HST UV Imaging Surveys
Dwarf galaxies (M*/M0 < 109) are the smallest and least luminous but most abundant galaxies in the universe. These galaxies are at the forefront of many important questions in galaxy formation theory, yet observationally we are only just beginning to constrain their physical properties, especially at high redshifts. Therefore, it is not surprising that JWST, Roman Telescope, and Euclid will be devoting some part of their time to study these galaxies via their stellar continuum and/or nebular emission lines at various redshifts.
In this talk, I will show how the combination of our deep UV imaging with WFC3/UVIS camera on HST and extensive spectroscopic observations with MOSFIRE spectrograph at the Keck observatory and grism data from WFC3 Infrared Spectroscopic Parallel Survey (WISP) allowed us to 1- observe dwarf galaxies at high redshifts (i.e., 1 (i.e., 1 < z < 3 ), which have always been below the detection limits of many surveys, and 2- better understand the formation and evolution of this population of galaxies via studying their number density evolution (i.e., luminosity function), star formation history (i.e., bursty SFH) and dust attenuation. In addition, I will introduce our new large UV imaging surveys with HST (UVCANDELS and UV Frontier Fields II), which will further explore the high-redshift dwarf galaxies. These UV surveys are vitally important because some of their primary science goals, such as studying the escaping ionizing radiation from galaxies, cannot fundamentally be studied by JWST. Relatedly, I will present our recent work of searching for escaping ionizing radiation from low-mass galaxies at high redshift.
Prof. Steven Longmore, Liverpool John Moores University, "Ecosystems and Life", Astronomy Seminar10:00am
Wednesday, December 2nd, 2020
10:00 AM - 11:00 AM
Storrs Campus onlineProf. Steven Longmore, Liverpool John Moores University
Ecosystems and Life
Abstract: I will cover two topics united under the theme of ecosystems shaping the potential for life. In the first half, I will present recent results showing that the architecture of planetary systems is shaped by their environmental ecosystems, in particular the degree of stellar clustering around their host star (Winter et al, 2020, Nature, 586, 528). We identify old, co-moving stellar groups around exoplanet host stars in the astrometric data from the Gaia satellite and demonstrate that the architecture of planetary systems exhibits a strong dependence on local stellar clustering in position-velocity phase space, implying a dependence on their formation or evolution environment. After controlling for host stellar age, mass, metallicity, and distance from the Sun, we obtain highly significant differences in planetary (system) properties between phase space overdensities and the field. The median semi-major axis and orbital period of planets in overdensities are 0.087 au and 9.6 days, respectively, compared to 0.81 au and 154 days for planets around field stars. 'Hot Jupiters' (massive, close-in planets) predominantly exist in stellar phase-space overdensities, strongly suggesting that their extreme orbits originate from environmental perturbations rather than internal migration or planet-planet scattering. Our findings suggest that stellar clustering is an important factor setting the architectures of planetary systems. In the second half of the talk, I will discuss how we are using astrophysics research techniques to help ecologists protect ecosystems, save critically endangered animal species, and stop peat forest fires that are a major contributor to climate change.
Webex link: https://uconn-cmr.webex.com/meet/cab16109
Dr. Vivienne Baldassare, Washington State Univeristy , "Searching for active galactic nuclei in low-mass galaxies via optical variability", Astronomy Seminar11:00am
Dr. Vivienne Baldassare, Washington State Univeristy , "Searching for active galactic nuclei in low-mass galaxies via optical variability", Astronomy Seminar
Wednesday, November 18th, 2020
11:00 AM - 12:00 PM
Storrs Campus onlineDr. Vivienne Baldassare, Washington State Univeristy
Searching for active galactic nuclei in low-mass galaxies via optical variability
The present-day population of supermassive black holes in low-mass galaxies offers a window into massive black hole formation in the early universe. While we cannot yet observe the formation of "black hole seeds" at high redshift, the fraction of small galaxies that host a supermassive black hole -- and the properties of those black holes -- are thought to depend on the mechanism by which they form. However, black holes in the smallest galaxies can be difficult to find, requiring creative new approaches. I will discuss recent work showing that long-term optical photometric variability in low-mass galaxies can identify active galactic nuclei that are missed by other selection techniques. I will present an analysis of the nuclear variability of more than 70,000 nearby galaxies and discuss our sample of low-mass, variability-selected supermassive black holes. Using this sample, we also begin to place meaningful constraints on the present-day black hole occupation fraction at low galaxy stellar masses.
Webex link: https://uconn-cmr.webex.com/meet/yah14006
Mohammad Akhshik, Department of Physics, University of Connecticut, "REQUIEM-2D: REsolving QUIEscent Magnified galaxies using strong gravitational lensing, 2D grism spectroscopy and multi-band photometry", Astronomy Seminar10:00am
Mohammad Akhshik, Department of Physics, University of Connecticut, "REQUIEM-2D: REsolving QUIEscent Magnified galaxies using strong gravitational lensing, 2D grism spectroscopy and multi-band photometry", Astronomy Seminar
Wednesday, November 4th, 2020
10:00 AM - 11:00 AM
Storrs Campus onlineMohammad Akhshik, Department of Physics, University of Connecticut
REQUIEM-2D: REsolving QUIEscent Magnified galaxies using strong gravitational lensing, 2D grism spectroscopy and multi-band photometry
Despite the tremendous progress that has been made in the last decade in studying massive high redshift (z~2) quiescent galaxies, their formation pathways and quenching mechanisms have not yet been established observationally. In my talk, I will review the REQUIEM^2D galaxy survey of eight strong lensed quiescent galaxies at z=1.6-2.9, our attempt to understand the formation scenarios of quiescent galaxies by analyzing the spatially resolved stellar populations with deep HST grism spectroscopy. After briefly reviewing our methodology, I will discuss the results from our REQUIEM^2D pilot target, MRG-S0851, a gravitationally lensed quintuply imaged massive compact red galaxy at z=1.9. Using our recovered ages and SFHs from the joint spectrophotometric analysis, along with trajectories in the UVJ and FUVVJ color-color diagrams, I show that MRG-S0851 is consistent with an early forming, slow quenched galaxy that is going through a centrally-concentrated rejuvenation phase.
Dr. Daniel Walker, Department of Physics, University of Connecticut
Uncovering the hidden star formation in the Milky Way's Central Molecular Zone
As our nearest "extreme environment", the Central Molecular Zone (CMZ, inner few hundred parsecs of our Galaxy) offers an ideal laboratory in which to study the extent to which the process of star formation is sensitive to differing environmental conditions. At a distance of just 8.1 kpc, we can study this process from Galactic scales all the way down to protostellar scales, something that is not possible in extragalactic analogues. In this talk, I will give an overview of our current understanding of star formation in this region of the Galaxy. I will then present some results from recent and ongoing projects that are transforming our view of the CMZ, and providing insight into key questions concerning the role of galactic environment in the star formation process.
Meeting Link: https://uconn-cmr.webex.com/meet/cab16109