Publications (20)
Overview of Indigenous rights and outer space for the IAU-CPS Policy Hub
Hilding Neilson
As part of the mission of the International Astronomical Union Centre for the Protection of the Dark and Quiet Sky from Satellite Constellation Interference (IAU-CPS) Policy Hub to…
X-ray Observations of the Peculiar Cepheid V473 Lyr Identify A Low-Mass Companion
Nancy Remage Evans, Ignazio Pillitteri, Laszlo Molnar +17
V473 Lyr is a classical Cepheid which is unique in having substantial amplitude variations with a period of approximately 3.3 years, thought to be similar to the Blazhko variations…
Identifying low-amplitude pulsating stars through microlensing observations
Sedighe Sajadian, Richard Ignace, Hilding Neilson
One possibility for detecting low-amplitude pulsational variations is through gravitational microlensing. During a microlensing event, the temporary brightness increase leads to im…
The Connection Between Pulsation, Mass Loss and Circumstellar Shells in Classical Cepheids
Hilding Neilson, Chow-Choong Ngeow, Shashi Kanbur +1
Recent observations of Cepheids using infrared interferometry and Spitzer photometry have detected the presence of circumstellar envelopes (CSE) of dust and it has been hypothesize…
Indigenous rights, peoples, and space exploration: A response to the Canadian Space Agency (CSA) Consulting Canadians on a framework for future space exploration activities
Hilding Neilson, E. E. ÄirkoviÄ
Canada is beginning to plan its next chapter of space exploration that includes sending humans back to the Moon and onwards to Mars. This includes understanding humanities place in…
Comparison of limb-darkening laws from plane-parallel and spherically-symmetric model stellar atmospheres
Hilding Neilson
Limb-darkening is a fundamental constraint for modeling eclipsing binary and planetary transit light curves. As observations, for example from Kepler, CoRot, and Most, become more…
A Native Hawaiian-led summary of the current impact of constructing the Thirty Meter Telescope on Maunakea
Sara Kahanamoku, Rosie 'Anolani Alegado, Aurora Kagawa-Viviani +6
Maunakea, the proposed site of the Thirty Meter Telescope (TMT), is a lightning-rod topic for Native Hawaiians, Hawaii residents, and the international astronomy community. In this…
Stellar Evolution with Pulsation-Driven Mass Loss: The Case of LMC Cepheids
Hilding Neilson, Norbert Langer, Matteo Cantiello
The Cepheid mass discrepancy, the difference between mass estimates from stellar pulsation and stellar evolution models, is a long standing challenge for the understanding of stell…
A Multi-Year Photopolarimetric Study of the Semi-Regular Variable V CVn and Identification of Analogue Sources
Hilding Neilson, Nicolaus Steenken, John Simpson +4
The semi-regular variable star V Canum Venaticorum (V CVn) is well-known for its unusual linear polarization position angle (PA). Decades of observing V CVn reveal a nearly constan…
X-rays in Cepheids: Identifying Low-Mass Companions of Intermediate-Mass Stars
Nancy Remage Evans, Scott Engle, Ignazio Pillitteri +12
X-ray observations have been made of a sample of 20 classical Cepheids, including two new observations (Polaris and {\it l} Car) reported here. The occurrence of X-ray flux around…
Investigating Opacity Modifications and Reaction Rate Uncertainties to Resolve the Cepheid Mass Discrepancy
Joyce A. Guzik, Ebraheem Farag, Jakub Ostrowski +4
Cepheid masses derived from pulsations or binary dynamics are generally lower than those derived from stellar evolution models. Recent efforts have been dedicated to investigating…
Indigenous knowledges and kinship as a model for our future in outer space
Hilding Neilson
Commercial endeavours have already compromised our relationship with space. The Artemis Accords are creating a framework that will commercialize the Moon and further impact that re…
Broadband Transmission Spectroscopy of the super-Earth GJ 1214b suggests a Low Mean Molecular Weight Atmosphere
Bryce Croll, Loic Albert, Ray Jayawardhana +4
We used WIRCam on CFHT to observe four transits of the super-Earth GJ 1214b in the near-infrared. For each transit we observed in two bands nearly-simultaneously by rapidly switchi…
Twinkle -- a small satellite spectroscopy mission for the next phase of exoplanet science
Ian Stotesbury, Billy Edwards, Jean-Francois Lavigne +35
With a focus on off-the-shelf components, Twinkle is the first in a series of cost competitive small satellites managed and financed by Blue Skies Space Ltd. The satellite is based…
Discovery of a rapid, luminous nova in NGC 300 by the KMTNet Supernova Program
John Antoniadis, Dae-Sik Moon, Yuan Qi Ni +3
We present the discovery of a rapidly evolving transient by the Korean Microlensing Telescope Network Supernova Program (KSP). KSP is a novel high-cadence supernova survey that off…
Weighing Betelgeuse: Measuring the mass of alpha Orionis from stellar limb-darkening
Hilding Neilson, John B. Lester, Xavier Haubois
Stellar limb-darkening is an important tool for constraining the properties of a stellar atmosphere. We present a novel method for relating the fundamental stellar parameters mass…
Modeling the Variable Polarization of epsilon Aurigae In and Out of Eclipse
Richard Ignace, Gary Henson, Hilding Neilson +1
The eclipsing binary epsilon Aur is unique in being a very long-period binary involving an evolved, variable F star and a suspected B main-sequence star enshrouded in an opaque cir…
Cepheid Period-Luminosity Relation from the AKARI Observations
Chow-Choong Ngeow, Yoshifusa Ita, Shashi M. Kanbur +3
In this paper, we derive the period-luminosity (P-L) relation for Large Magellanic Cloud (LMC) Cepheids based on mid-infrared AKARI observations. AKARI's IRC sources were matched t…
X-rays in Cepheids: XMM-Newton Observations of Aql
Nancy Remage Evans, Ignazio Pillitteri, Pierre Kervella +13
X-ray bursts have recently been discovered in the Cepheids Cep and Dor modulated by the pulsation cycle. We have obtained an observation of the Cepheid Aql with the…
Wesenheit Function for Galactic Cepheids: Application to the Projection Factors
Chow-Choong Ngeow, Hilding Neilson, Nicolas Nardetto +1
Galactic Cepheids are necessary tools for calibrating the period-luminosity relation, but distances to individual Galactic Cepheids are difficult to precisely measure and are limit…