972 citations · 2.3k across the 36 of their papers we have counts for
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The dependence of HII region properties on global and local surface brightness within galaxy discs
J. F. Helmboldt, R. A. M. Walterbos, G. D. Bothun +2
Using B, R, and H-alpha images of roughly equal-sized samples of low surface brightness (LSB) and high surface brightness (HSB) galaxies (~40 galaxies apiece), we have explored the…
A shrinking Compact Symmetric Object: J11584+2450?
S. E. Tremblay, G. B. Taylor, J. F. Helmboldt +2
We present multi-frequency multi-epoch Very Long Baseline Array (VLBA) observations of J11584+2450. These observations clearly show this source, previously classified as a core-jet…
Current star formation in early-type galaxies and the K+A phenomenon
J. F. Helmboldt, R. A. M. Walterbos, T. Goto
We present the results of an effort to identify and study a sample of the likely progenitors of elliptical (E) and lenticular (S0) K+A galaxies. To achieve this, we have searched a…
A Statistical Description of AGN Jet Evolution from the VLBA Imaging and Polarimetry Survey (VIPS)
J. F. Helmboldt, G. B. Taylor, R. C. Walker +1
A detailed analysis of the evolution of the properties of core-jet systems within the VLBA Imaging and Polarimetry Survey (VIPS) is presented. We find a power-law relationship betw…
Characteristics of EGRET Blazars in the VLBA Imaging and Polarimetry Survey (VIPS)
G. B. Taylor, S. E. Healey, J. F. Helmboldt +12
We examine the radio properties of EGRET-detected blazars observed as part of the VLBA Imaging and Polarimetry Survey (VIPS). VIPS has a flux limit roughly an order of magnitude be…
Radio Frequency Spectra of 388 Bright 74 MHz Sources
J. F. Helmboldt, N. E. Kassim, A. S. Cohen +2
As a service to the community, we have compiled radio frequency spectra from the literature for all sources within the VLA Low Frequency Sky Survey (VLSS) that are brighter than 15…