Publications

NASA ADS Compilation

Direct supervision/mentoring by N. Nielsen: students and postdocs.

Submitted

  1. The chemodynamical signature of coherent metal-poor inflow and enriched recycled accretion in the cool circumgalactic medium
    Kacprzak, G. G., Doran, J., Sameer, Farrington, J., Charlton, J. C., Nielsen, N. M., Gupta, K. R., Churchill, C. W., Barone, T. M., & Fernández-Figueroa, A. 2026, MNRAS, submitted
  2. 13 Billion Years of MgII Absorber Evolution
    Churchill, C. W., Abbas, A., Kacprzak, G. G., & Nielsen, N. M. 2026, ApJ, submitted

Refereed

    First Author

  1. An emission map of the disk–circumgalactic medium transition in starburst IRAS 08339+6517
    Nielsen, N. M., Fisher, D. B., Kacprzak, G. G., Chisholm, J., Martin, D. C., Reichardt Chu, B., Sandstrom, K. M., & Rickards Vaught, R. J. 2024, Nature Astronomy, 8, 1602
  2. A Complex Multiphase DLA Associated with a Compact Group at z=2.431 Traces Accretion, Outflows, and Tidal Streams
    Nielsen, N. M., Kacprzak, G. G., Sameer, Murphy, M. T., Nateghi, H., Charlton, J. C., & Churchill, C. W. 2022, MNRAS, 514, 6074
  3. The CGM at Cosmic Noon with KCWI: Outflows from a Star-forming Galaxy at z=2.071
    Nielsen, N. M., Kacprzak, G. G., Pointon, S. K., Murphy, M. T., Churchill, C. W., & Davé, R. 2020, ApJ, 904, 164
  4. MAGIICAT VI. The MgII Intragroup Medium is Kinematically Complex
    Nielsen, N. M., Kacprzak, G. G., Pointon, S. K., Churchill, C. W., & Murphy, M. T. 2018, ApJ, 869, 153
  5. The Highly Ionized Circumgalactic Medium is Kinematically Uniform Around Galaxies
    Nielsen, N. M., Kacprzak, G. G., Muzahid, S., Churchill, C. W., Murphy, M. T., & Charlton, J. C. 2017, ApJ, 834, 148
  6. MAGIICAT IV. Kinematics of the Circumgalactic Medium and Evidence for Quiescent Evolution Around Red Galaxies
    Nielsen, N. M., Churchill, C. W., Kacprzak, G. G., Murphy, M. T., & Evans, J. L. 2016, ApJ, 818, 171
  7. MAGIICAT V. Orientation of Outflows and Accretion Determine the Kinematics and Column Densities of the Circumgalactic Medium
    Nielsen, N. M., Churchill, C. W., Kacprzak, G. G., Murphy, M. T., & Evans, J. L. 2015, ApJ, 812, 83
  8. MAGIICAT II. General Characteristics of the MgII Absorbing Circumgalactic Medium
    Nielsen, N. M., Churchill, C. W., & Kacprzak, G. G. 2013, ApJ, 776, 115
  9. MAGIICAT I. The MgII Absorber-Galaxy Catalog
    Nielsen, N. M., Churchill, C. W., Kacprzak, G. G., & Murphy, M. T. 2013, ApJ, 776, 114

    10. Co-author

  10. The AGEL Survey Data Release 2: A Gravitational Lens Sample for Galaxy Evolution and Cosmology
    Barone, T. M., et al., including Nielsen, N. M. 2026, AJ, 171, 57
  11. Ultra-strong MgII absorbers trace both inflowing and outflowing gas: insights from dual down-the-barrel and quasar sightlines
    Fernández-Figueroa, A., Kacprzak, G. G., Barone, T. M., Nielsen, N. M., Rubin, K. H. R., Pitts, A. J., & Mazzilli Ciraulo, B. 2025, MNRAS, 544, 255
  12. COS-EDGES: Co-rotation and Kinematic Stratification of the Multi-Phase CGM Around Edge-On Galaxies
    Kacprzak, G. G., Oppenheimer, B. D., Nielsen, N. M., Fernández-Figueroa, A., Murphy, M. T., Allen, R. J., Barone, T. M., Sameer, Churchill, C. W., Burchett, J. N., Gupta, K. R., Charlton, J. C., & Platukis, C. B. 2025, PASA, 42, 128
  13. DUVET: sub-kiloparsec resolved star formation driven outflows in a sample of local starbursting disk galaxies
    Reichardt Chu, B., Fisher, D. B., Chisholm, J., Berg, D., Bolatto, A., Cameron, A. J., Fielding, D. B., Herrera-Camus, R., Kacprzak, G. G., Li, M., McLeod, A. F., McPherson, D. K., Nielsen, N. M., Rickards Vaught, R. J., Ridolfo, S. G., & Sandstrom, K. M. 2025, MNRAS, 536, 1799
  14. Signatures of Gas Flows - II: Connecting the kinematics of the multiphase circumgalactic medium to galaxy rotation
    Nateghi, H., Kacprzak, G. G., Nielsen, N. M., Sameer, Murphy, M. T., Churchill, C. W., & Charlton, J. C. 2024, MNRAS, 534, 930
  15. Gravitational lensing reveals cool gas within 10–20 kpc around a quiescent galaxy
    Barone, T. M., Kacprzak, G. G., Nightingale, J. W., Nielsen, N. M., Glazebrook, K., Tran, K.-V. H., Jones, T., Nateghi, H., Vasan G. C., K., Sahu, N., Nanayakkara, T., Skobe, H., van de Sande, J., Lopez, S., & Lewis, G. F. 2024, Communications Physics, 7, 268
  16. Signatures of gas flows - I: Connecting the kinematics of the HI circumgalactic medium to galaxy rotation
    Nateghi, H., Kacprzak, G. G., Nielsen, N. M., Murphy, M. T., Churchill, C. W., Muzahid, S., Sameer, & Charlton, J. C. 2024, MNRAS, 533, 1321
  17. Unveiling the Complex Circumgalactic Medium: A Comparative Study of Merging and Non-Interacting Galaxy Groups
    Fernández-Figueroa, A., Kacprzak, G. G., Nielsen, N. M., Barone, T. M., Nateghi, H., Sameer, Fisher, D. B., & Reichardt Chu, B. 2024, MNRAS, 531, 3658
  18. DUVET: Resolved direct metallicity measurements in the outflow of starburst galaxy NGC 1569
    Hamel-Bravo, M. J., Fisher, D. B., Berg, D., Björgvinsson, B., Bolatto, A., Cameron, A. J., Chisholm, J., Fielding, D. B., Herrera-Camus, R., Kacprzak, G. G., Li, M., Mazzilli Ciraulo, B., McLeod, A. F., McPherson, D. K., Nielsen, N. M., Reichardt Chu, B., Rickards Vaught, R. J., & Sandstrom, K. M. 2024, MNRAS, 530, 3855
  19. Cloud-by-cloud Multiphase Investigation of the Circumgalactic Medium of Low-redshift Galaxies
    Sameer, Charlton, J. C., Wakker, B. P., Kacprzak, G. G., Nielsen, N. M., Churchill, C. W., Richter, P., Muzahid, S., Ho, S. H., Nateghi, H., Rosenwasser, B., Narayanan, A., & Ganguly, R. 2024, MNRAS, 530, 3827
  20. Examining quasar absorption-line analysis methods: the tension between simulations and observational assumptions key to modelling clouds
    Marra, R., Churchill, C. W., Kacprzak, G. G., Nielsen, N. M., Trujillo-Gomez, S., & Lewis, E. 2024, MNRAS, 527, 10522
  21. DUVET Survey: Mapping Outflows in the Metal-Poor Starburst Mrk 1486
    McPherson, D. K., Fisher, D. B., Nielsen, N. M., Kacprzak, G. G., Reichardt Chu, B., Cameron, A. J., Bolatto, A. D., Chisholm, J., Fielding, D. B., Berg, D., Herrera-Camus, R., Li, M., Rickards Vaught, R. J., & Sandstrom, K. 2023, MNRAS, 525, 6170
  22. DUVET: Spatially Resolved Observations of Star Formation Regulation via Galactic Outflows in a Starbursting Disk Galaxy
    Reichardt Chu, B., Fisher, D. B., Bolatto, A. D., Chisholm, J., Fielding, D., Berg, D., Cameron, A. J., Glazebrook, K., Herrera-Camus, R., Kacprzak, G. G., Lenkić, L., Li, M., McPherson, D. K., Nielsen, N. M., Obreschkow, D., Rickards Vaught, R. J., & Sandstrom, K. 2022, ApJ, 941, 163
  23. The DUVET Survey: Resolved Maps of Star Formation Outflows in a Compact, Starbursting Galaxy
    Reichardt Chu, B., Fisher, D. B., Nielsen, N. M., Chisholm, J., Girard, M., Kacprzak, G. G., Bolatto, A., Herrera-Camus, R., Sandstrom, K., Li, M., Rickards Vaught, R., & McPherson, D. K. 2022, MNRAS, 511, 5782
  24. Extreme Variation in Star Formation Efficiency across a Compact, Starbursting Disk Galaxy
    Fisher, D. B., Bolatto, A. D., Glazebrook, K., Obreschkow, D., Abraham, R. G., Kacprzak, G. G., & Nielsen, N. M. 2022, ApJ, 928, 169
  25. Probing the physicochemical properties of the Leo Ring and the Leo I group
    Sameer, Charlton, J. C., Kacprzak, G. G., Narayanan, A., Sankar, S., Richter, P., Wakker, B. P., Nielsen, N. M., & Churchill, C. W. 2022, MNRAS, 510, 5796
  26. Evolution of CIV Absorbers. II. Where does CIV live?
    Hasan, F., Churchill, C. W., Stemock, B., Nielsen, N. M., Kacprzak, G. G., Croom, M., & Murphy, M. T. 2022, ApJ, 924, 12
  27. Using cosmological simulations and synthetic absorption spectra to assess the accuracy of observationally derived CGM metallicities
    Marra, R., Churchill, C. W., Doughty, C., Kacprzak, G. G., Charlton, J. C., Sameer, Nielsen, N. M., Ceverino, D., & Trujillo-Gomez, S. 2021, MNRAS, 508, 4938
  28. The DUVET Survey: Direct Te-based Metallicity Mapping of Metal-enriched Outflows and Metal-poor Inflows in Markarian 1486
    Cameron, A. J., Fisher, D. B., McPherson, D., Kacprzak, G. G., Berg, D. A., Bolatto, A., Chisholm, J., Herrera-Camus, R., Nielsen, N. M., Reichardt Chu, B., Rickards Vaught, R. J., Sandstrom, K, & Trenti, M. 2021, ApJL, 918, L16
  29. Spatial Distribution of OVI Covering Fractions in the Simulated Circumgalactic Medium
    Marra, R., Churchill, C. W., Kacprzak, G. G., Vander Vliet, R. P., Ceverino, D., Lewis, E., Nielsen, N. M., Muzahid, S., & Charlton, J. C. 2021, ApJ, 907, 8
  30. Cloud-by-cloud, multiphase, Bayesian modeling: Application to four weak, low ionization absorbers
    Sameer, Charlton, J. C., Norris, J. M., Gebhardt, M., Churchill, C. W., Kacprzak, G. G., Muzahid, S., Narayanan, A., Nielsen, N. M., Richter, P., & Wakker, B. 2021, MNRAS, 501, 2112
  31. Disentangling the multi-phase circumgalactic medium shared between a dwarf and a massive star-forming galaxy at z~0.4
    Nateghi, H., Kacprzak, G. G., Nielsen, N. M., Muzahid, S., Churchill, C. W., Pointon, S. K., & Charlton, J. C. 2021, MNRAS, 500, 3987
  32. Evidence for galaxy quenching in the green valley caused by a lack of a circumgalactic medium
    Kacprzak, G. G., Nielsen, N. M., Nateghi, H., Churchill, C. W., Pointon, S. K., Nanayakkara, T., Muzahid, S., & Charlton, J. C. 2021, MNRAS, 500, 2289
  33. Evolution of CIV Absorbers. I. The Cosmic Incidence
    Hasan, F., Churchill, C. W., Stemock, B., Mathes, N. L., Nielsen, N. M., Finlator, K., Doughty, C., Croom, M., Kacprzak, G. G., & Murphy, M. T. 2020, ApJ, 904, 44
  34. MgII Absorbers in High-Resolution Quasar Spectra. I. Voigt Profile Models
    Churchill, C. W., Evans, J. L., Stemock, B., Nielsen, N. M., Kacprzak, G. G., & Murphy, M. T. 2020, ApJ, 904, 28
  35. Low-mass Group Environments Have No Substantial Impact on the Circumgalactic Medium Metallicity
    Pointon, S. K., Kacprzak, G. G., Nielsen, N. M., Murphy, M. T., Muzahid, S., Churchill, C. W., & Charlton, J. C. 2020, AJ, 159, 216
  36. The Relationship between Galaxy ISM and Circumgalactic Gas Metallicities
    Kacprzak, G. G., Pointon, S. K., Nielsen, N. M., Churchill, C. W., Muzahid, S., & Charlton, J. C. 2019, ApJ, 886, 91
  37. Kinematics of the OVI Circumgalactic Medium: Halo Mass Dependence and Outflow Signatures
    Ng, M., Nielsen, N. M., Kacprzak, G. G., Pointon, S. K., Muzahid, S., Churchill, C. W., & Charlton, J. C. 2019, ApJ, 886, 66
  38. Relationship between the Metallicity of the Circumgalactic Medium and Galaxy Orientation
    Pointon, S. K., Kacprzak, G. G., Nielsen, N. M., Muzahid, S., Murphy, M. T., Churchill, C. W., & Charlton, J. C. 2019, ApJ, 883, 78
  39. Io's Volcanic Activity from Time Domain Adaptive Optics Observations: 2013-2018
    de Kleer, K., de Pater, I., Molter, E. M., Banks, E., Davies, A. G., Alvarez, C., Campbell, R., Aycock, J., Pelletier, J., Stickel, T., Kacprzak, G. G., Nielsen, N. M., Stern, D., & Tollefson, J. 2019, AJ, 158, 29
  40. The Relation between Galaxy ISM and Circumgalactic OVI Gas Kinematics Derived from Observations and ΛCDM Simulations
    Kacprzak, G. G., Vander Vliet, R. P., Nielsen, N. M., Muzahid, S., Pointon, S. K., Churchill, C. W., Ceverino, D., Arraki, K. S., Klypin, A., Charlton, J. C., & Lewis, E. 2019, ApJ, 870, 137
  41. The Impact of the Group Environment on the OVI Circumgalactic Medium
    Pointon, S. K., Nielsen, N. M., Kacprzak, G. G., Muzahid, S., Churchill, C. W., & Charlton, J. C. 2017, ApJ, 844, 23
  42. The Azimuthal Dependence of Outflows and Accretion Detected Using OVI Absorption
    Kacprzak, G. G., Muzahid, S., Churchill, C. W., Nielsen, N. M., & Charlton, J. C. 2015, ApJ, 815, 22
  43. An Extreme Metallicity, Large-Scale Outflow from a Star-Forming Galaxy at z~0.4
    Muzahid, S., Kacprzak, G. G., Churchill, C. W., Charlton, J. C., Nielsen, N. M., Mathes, N. L., & Trujillo-Gomez, S. 2015, ApJ, 811, 132
  44. Halo Mass Dependence of HI and OVI Absorption: Evidence for Differential Kinematics
    Mathes, N. L., Churchill, C. W., Kacprzak, G. G., Nielsen, N. M., Trujillo-Gomez, S., Charlton, J., & Muzahid, S. 2014, ApJ, 792, 128
  45. MAGIICAT III. Interpreting Self-Similarity of the Circumgalactic Medium with Virial Mass Using MgII Absorption
    Churchill, C. W., Trujillo-Gomez, S., Nielsen, N. M., & Kacprzak, G. G. 2013, ApJ, 779, 87
  46. The Smooth MgII Gas Distribution Through the Interstellar/Extra-planar/Halo Interface
    Kacprzak, G. G., Cooke, J., Churchill, C. W., Ryan-Weber, E. V., & Nielsen, N. M. 2013, ApJ, 777, L11
  47. The Redshift Distribution of Intervening Weak MgII Quasar Absorbers and a Curious Dependence on Quasar Luminosity
    Evans, J. L., Churchill, C. W., Murphy, M. T., Nielsen, N. M., & Klimek, E. S. 2013, ApJ, 768, 3
  48. The Self-Similarity of the Circumgalactic Medium with Galaxy Virial Mass: Implications for Cold-Mode Accretion
    Churchill, C. W., Nielsen, N. M., Kacprzak, G. G., & Trujillo-Gomez, S. 2013, ApJ, 763, L42
  49. Tracing Outflows and Accretion: A Bimodal Azimuthal Dependence of MgII Absorption
    Kacprzak, G. G., Churchill, C. W., & Nielsen, N. M. 2012, ApJ, 760, L7
  50. Quenched Accretion of a Large Scale Metal-Poor Filament due to Virial Shocking in the Halo of a Massive z=0.7 Galaxy
    Churchill, C. W., Kacprzak, G. G., Steidel, C. C., Spitler, L. R., Holtzman, J. A., Nielsen, N. M., & Trujillo-Gomez, S. 2012, ApJ, 760, 68

Conference Proceedings

  1. Mapping the transition between the ISM and the CGM
    Nielsen, N. M., Fisher, D. B., Kacprzak, G. G., Chisholm, J., Martin, D. C., Reichardt Chu, B., Sandstrom, K., Rickards Vaught, R., & DUVET Team 2024, in Resolving the Circumgalactic Medium and its Impact on Galaxy Evolution, 2
  2. Gas accretion along the edges of galaxies
    Kacprzak, G. G., Nielsen, N. M., Fernández-Figeroa, A., Barone, T. M., Nateghi, H., Oppenheimer, B., Murphy, M. T., Churchill, C. W., & Charlton, J. C. 2024, in Resolving the Circumgalactic Medium and its Impact on Galaxy Evolution, 42
  3. Unveiling the cool CGM around quiescent galaxies with galaxy-galaxy lensing
    Barone, T. M., Kacprzak, G. G., Nielsen, N. M., & Lopez, S. 2024 in Resolving the Circumgalactic Medium and its Impact on Galaxy Evolution, 27
  4. Gas Kinematics in the Multiphase Circumgalactic Medium
    Nielsen, N. M., Kacprzak, G. G., Churchill, C. W., Murphy, M. T., Muzahid, S., Charlton, J. C., & Evans, J. L. 2017, in IAU Symposium 321, Formation and Evolution of Galaxy Outskirts, ed. A. Gil de Paz, J. H. Knapen, & J. C. Lee, 345
  5. HST Observations Reveal the Curious Geometry of Circumgalactic Gas
    Kacprzak, G. G., Muzahid, S., Churchill, C. W., Nielsen, N. M., & Charlton, J. C. 2017, in IAU Symposium 321, Formation and Evolution of Galaxy Outskirts, ed. A. Gil de Paz, J. H. Knapen, & J. C. Lee, 342
  6. HST Observations Reveal the Curious Geometry of Circumgalactic Gas
    Kacprzak, G. G., Muzahid, S., Churchill, C. W., Nielsen, N. M., & Charlton, J. C. 2016, in The Interplay between Local and Global Processes in Galaxies, ed. S. F. Sanchez, C. Morisset, & G. Delgado-Inglada, 26