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86 results on '"Mack, K. J."'

1. Recoil imaging for directional detection of dark matter, neutrinos, and physics beyond the Standard Model

Author

O'Hare, C. A. J., Loomba, D., Altenmüller, K., Álvarez-Pol, H., Amaro, F. D., Araújo, H. M., Sierra, D. Aristizabal, Asaadi, J., Attié, D., Aune, S., Awe, C., Ayyad, Y., Baracchini, E., Barbeau, P., Battat, J. B. R., Bell, N. F., Biasuzzi, B., Bignell, L. J., Boehm, C., Bolognino, I., Brunbauer, F. M., Caamaño, M., Cabo, C., Caratelli, D., Carmona, J. M., Castel, J. F., Cebrián, S., Cogollos, C., Collison, D., Costa, E., Dafni, T., Dastgiri, F., Deaconu, C., De Romeri, V., Desch, K., Dho, G., Di Giambattista, F., Díez-Ibáñez, D., D'Imperio, G., Dutta, B., Eldridge, C., Elliott, S. R., Ezeribe, A. C., Fava, A., Felkl, T., Fernández-Domínguez, B., Ribas, E. Ferrer, Flöthner, K. J., Froehlich, M., Galán, J., Galindo, J., García, F., Pascual, J. A. García, Gelli, B. P., Ghrear, M., Giomataris, Y., Gnanvo, K., Gramellini, E., Di Cortona, G. Grilli, Hall-Wilton, R., Harton, J., Hedges, S., Higashino, S., Hill, G., Holanda, P. C., Ikeda, T., Irastorza, I. G., Jackson, P., Janssens, D., Jones, B., Kaminski, J., Katsioulas, I., Kelly, K., Kemmerich, N., Kemp, E., Korandla, H. B., Kraus, H., Lackner, A., Lane, G. J., Lewis, P. M., Lisowska, M., Luzón, G., Lynch, W. A., Maccarrone, G., Mack, K. J., Majewski, P. A., Mano, R. D. P., Margalejo, C., Markoff, D., Marley, T., Marques, D. J. G., Massarczyk, R., Mazzitelli, G., McCabe, C., McKie, L. J., McLean, A. G., McNamara, P. C., Mei, Y., Messina, A., Mills, A. F., Mirallas, H., Miuchi, K., Monteiro, C. M. B., Mosbech, M. R., Muller, H., da Luz, H. Natal, Nakamura, K. D., Natochii, A., Neep, T., Newstead, J. L., Nikolopoulos, K., Obis, L., Oliveri, E., Orlandini, G., de Solórzano, A. Ortiz, von Oy, J., Papaevangelou, T., Pérez, O., Perez-Gonzalez, Y. F., Pfeiffer, D., Phan, N. S., Piacentini, S., Olloqui, E. Picatoste, Pinci, D., Popescu, S., Prajapati, A., Queiroz, F. S., Raaf, J. L., Resnati, F., Ropelewski, L., Roque, R. C., Ruiz-Choliz, E., Rusu, A., Ruz, J., Samarati, J., Santos, E. M., Santos, J. M. F. dos, Sauli, F., Scharenberg, L., Schiffer, T., Schmidt, S., Scholberg, K., Schott, M., Schueler, J., Segui, L., Sekiya, H., Sengupta, D., Slavkovska, Z., Snowden-Ifft, D., Soffitta, P., van Stenis, M., Spooner, N. J. C., Strigari, L., Stuchbery, A. E., Sun, X., Torelli, S., Tilly, E. G., Thomas, A. W., Thorpe, T. N., Urquijo, P., Utrobičić, A., Vahsen, S. E., Veenhof, R., Vogel, J. K., Williams, A. G., Wood, M. H., and Zettlemoyer, J.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

Recoil imaging entails the detection of spatially resolved ionization tracks generated by particle interactions. This is a highly sought-after capability in many classes of detector, with broad applications across particle and astroparticle physics. However, at low energies, where ionization signatures are small in size, recoil imaging only seems to be a practical goal for micro-pattern gas detectors. This white paper outlines the physics case for recoil imaging, and puts forward a decadal plan to advance towards the directional detection of low-energy recoils with sensitivity and resolution close to fundamental performance limits. The science case covered includes: the discovery of dark matter into the neutrino fog, directional detection of sub-MeV solar neutrinos, the precision study of coherent-elastic neutrino-nucleus scattering, the detection of solar axions, the measurement of the Migdal effect, X-ray polarimetry, and several other applied physics goals. We also outline the R&D programs necessary to test concepts that are crucial to advance detector performance towards their fundamental limit: single primary electron sensitivity with full 3D spatial resolution at the $\sim$100 micron-scale. These advancements include: the use of negative ion drift, electron counting with high-definition electronic readout, time projection chambers with optical readout, and the possibility for nuclear recoil tracking in high-density gases such as argon. We also discuss the readout and electronics systems needed to scale-up such detectors to the ton-scale and beyond., Comment: 77 pages, 20 figures. Submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)

Published
2022

2. CYGNUS: Feasibility of a nuclear recoil observatory with directional sensitivity to dark matter and neutrinos

Author

Vahsen, S. E., O'Hare, C. A. J., Lynch, W. A., Spooner, N. J. C., Baracchini, E., Barbeau, P., Battat, J. B. R., Crow, B., Deaconu, C., Eldridge, C., Ezeribe, A. C., Ghrear, M., Loomba, D., Mack, K. J., Miuchi, K., Mouton, F. M., Phan, N. S., Scholberg, K., and Thorpe, T. N.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

Now that conventional weakly interacting massive particle (WIMP) dark matter searches are approaching the neutrino floor, there has been a resurgence of interest in detectors with sensitivity to nuclear recoil directions. A large-scale directional detector is attractive in that it would have sensitivity below the neutrino floor, be capable of unambiguously establishing the galactic origin of a purported dark matter signal, and could serve a dual purpose as a neutrino observatory. We present the first detailed analysis of a 1000 m$^3$-scale detector capable of measuring a directional nuclear recoil signal at low energies. We propose a modular and multi-site observatory consisting of time projection chambers (TPCs) filled with helium and SF$_6$ at atmospheric pressure. Depending on the TPC readout technology, 10-20 helium recoils above 6 keVr or only 3-4 recoils above 20 keVr would suffice to distinguish a 10 GeV WIMP signal from the solar neutrino background. High-resolution charge readout also enables powerful electron background rejection capabilities well below 10 keV. We detail background and site requirements at the 1000 m$^3$-scale, and identify materials that require improved radiopurity. The final experiment, which we name CYGNUS-1000, will be able to observe 10-40 neutrinos from the Sun, depending on the final energy threshold. With the same exposure, the sensitivity to spin independent cross sections will extend into presently unexplored sub-10 GeV parameter space. For spin dependent interactions, already a 10 m$^3$-scale experiment could compete with upcoming generation-two detectors, but CYGNUS-1000 would improve upon this considerably. Larger volumes would bring sensitivity to neutrinos from an even wider range of sources, including galactic supernovae, nuclear reactors, and geological processes., Comment: 64 pages, 34 figures

Published
2020

3. The Cosmic Dawn and Epoch of Reionization with the Square Kilometre Array

Author

Koopmans, L. V. E., Pritchard, J., Mellema, G., Abdalla, F., Aguirre, J., Ahn, K., Barkana, R., van Bemmel, I., Bernardi, G., Bonaldi, A., Briggs, F., de Bruyn, A. G., Chang, T. C., Chapman, E., Chen, X., Ciardi, B., Datta, K. K., Dayal, P., Ferrara, A., Fialkov, A., Fiore, F., Ichiki, K., Illiev, I. T., Inoue, S., Jelić, V., Jones, M., Lazio, J., Maio, U., Majumdar, S., Mack, K. J., Mesinger, A., Morales, M. F., Parsons, A., Pen, U. -L., Santos, M., Schneider, R., Semelin, B., de Souza, R. S., Subrahmanyan, R., Takeuchi, T., Trott, C., Vedantham, H., Wagg, J., Webster, R., and Wyithe, S.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Concerted effort is currently ongoing to open up the Epoch of Reionization (EoR) ($z\sim$15-6) for studies with IR and radio telescopes. Whereas IR detections have been made of sources (Lyman-$\alpha$ emitters, quasars and drop-outs) in this redshift regime in relatively small fields of view, no direct detection of neutral hydrogen, via the redshifted 21-cm line, has yet been established. Such a direct detection is expected in the coming years, with ongoing surveys, and could open up the entire universe from $z\sim$6-200 for astrophysical and cosmological studies, opening not only the EoR, but also its preceding Cosmic Dawn ($z\sim$30-15) and possibly even the later phases of the Dark Ages ($z\sim$200-30). All currently ongoing experiments attempt statistical detections of the 21-cm signal during the EoR, with limited signal-to-noise. Direct imaging, except maybe on the largest (degree) scales at lower redshifts, as well as higher redshifts will remain out of reach. The Square Kilometre Array(SKA) will revolutionize the field, allowing direct imaging of neutral hydrogen from scales of arc-minutes to degrees over most of the redshift range $z\sim$6-28 with SKA1-LOW, and possibly even higher redshifts with the SKA2-LOW. In this SKA will be unique, and in parallel provide enormous potential of synergy with other upcoming facilities (e.g. JWST). In this chapter we summarize the physics of 21-cm emission, the different phases the universe is thought to go through, and the observables that the SKA can probe, referring where needed to detailed chapters in this volume (Abridged)., Comment: Accepted for publication in the SKA Science Book 'Advancing Astrophysics with the Square Kilometre Array', to appear in 2015. PoS(AASKA14)001

Published
2015
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4. The Dependence of the $A_V$ Prior for SN\,Ia on Host Mass and Disk Inclination

Author

Holwerda, B. W., Keel, W. C., Kenworthy, M. A., and Mack, K. J.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Supernovae type Ia (SNIa) are used as "standard candles" for cosmological distance scales. To fit their light curve shape -- absolute luminosity relation, one needs to assume an intrinsic color and a likelihood of host galaxy extinction or a convolution of these, a color distribution prior. The host galaxy extinction prior is typically assumed to be an exponential drop-off for the current supernova programs ($P(A_V) \propto e^{-A_V/\tau_0}$). We explore the validity of this prior using the distribution of extinction values inferred when two galaxies accidentally overlap (an occulting galaxy pair). We correct the supernova luminosity distances from the SDSS-III Supernova projects (SDSS-SN) by matching the host galaxies to one of three templates from occulting galaxy pairs based on the host galaxy mass and the $A_V$-bias - prior-scale ($\tau_0$) relation from Jha et al. (2007). We find that introducing an $A_V$ prior that depends on host mass results in lowered luminosity distances for the SDSS-SN on average but it does not reduce the scatter in individual measurements. This points, in our view, to the need for many more occulting galaxy templates to match to SNIa host galaxies to rule out this possible source of scatter in the SNIa distance measurements. We match occulting galaxy templates based on both mass and projected radius and we find that one should match by stellar mass first with radius as a secondary consideration. We discuss the caveats of the current approach and our aim is to convince the reader that a library of occulting galaxy pairs observed with HST will provide sufficient priors to improve (optical) SNIa measurements to the next required accuracy in Cosmology., Comment: 11 figures, 2 tables, accepted by MNRAS

Published
2015

5. Recoil imaging for dark matter, neutrinos, and physics beyond the Standard Model

Author

O'Hare, C. A. J., Loomba, D., Altenmüller, K., Álvarez-Pol, H., Amaro, F. D., Araújo, H. M., Sierra, D. Aristizabal, Asaadi, J., Attié, D., Aune, S., Awe, C., Ayyad, Y., Baracchini, E., Barbeau, P., Battat, J. B. R., Bell, N. F., Biasuzzi, B., Bignell, L. J., Boehm, C., Bolognino, I., Brunbauer, F. M., Caamaño, M., Cabo, C., Caratelli, D., Carmona, J. M., Castel, J. F., Cebrián, S., Cogollos, C., Collison, D., Costa, E., Dafni, T., Dastgiri, F., Deaconu, C., De Romeri, V., Desch, K., Dho, G., Di Giambattista, F., Díez-Ibáñez, D., D'Imperio, G., Dutta, B., Eldridge, C., Elliott, S. R., Ezeribe, A. C., Fava, A., Felkl, T., Fernández-Domínguez, B., Ribas, E. Ferrer, Flöthner, K. J., Froehlich, M., Galán, J., Galindo, J., García, F., Pascual, J. A. García, Gelli, B. P., Ghrear, M., Giomataris, Y., Gnanvo, K., Gramellini, E., Di Cortona, G. Grilli, Hall-Wilton, R., Harton, J., Hedges, S., Higashino, S., Hill, G., Holanda, P. C., Ikeda, T., Irastorza, I. G., Jackson, P., Janssens, D., Jones, B., Kaminski, J., Katsioulas, I., Kelly, K., Kemmerich, N., Kemp, E., Korandla, H. B., Kraus, H., Lackner, A., Lane, G. J., Lewis, P. M., Lisowska, M., Luzón, G., Lynch, W. A., Maccarrone, G., Mack, K. J., Majewski, P. A., Mano, R. D. P., Margalejo, C., Markoff, D., Marley, T., Marques, D. J. G., Massarczyk, R., Mazzitelli, G., McCabe, C., McKie, L. J., McLean, A. G., McNamara, P. C., Mei, Y., Messina, A., Mills, A. F., Mirallas, H., Miuchi, K., Monteiro, C. M. B., Mosbech, M. R., Muller, H., da Luz, H. Natal, Nakamura, K. D., Natochii, A., Neep, T., Newstead, J. L., Nikolopoulos, K., Obis, L., Oliveri, E., Orlandini, G., de Solórzano, A. Ortiz, von Oy, J., Papaevangelou, T., Pérez, O., Perez-Gonzalez, Y. F., Pfeiffer, D., Phan, N. S., Piacentini, S., Olloqui, E. Picatoste, Pinci, D., Popescu, S., Prajapati, A., Queiroz, F. S., Raaf, J. L., Resnati, F., Ropelewski, L., Roque, R. C., Ruiz-Choliz, E., Rusu, A., Ruz, J., Samarati, J., Santos, E. M., Santos, J. M. F. dos, Sauli, F., Scharenberg, L., Schiffer, T., Schmidt, S., Scholberg, K., Schott, M., Schueler, J., Segui, L., Sekiya, H., Sengupta, D., Slavkovska, Z., Snowden-Ifft, D., Soffitta, P., van Stenis, M., Spooner, N. J. C., Strigari, L., Stuchbery, A. E., Sun, X., Torelli, S., Tilly, E. G., Thomas, A. W., Thorpe, T. N., Urquijo, P., Utrobičić, A., Vahsen, S. E., Veenhof, R., Vogel, J. K., Williams, A. G., Wood, M. H., Zettlemoyer, J., O'Hare, C. A. J., Loomba, D., Altenmüller, K., Álvarez-Pol, H., Amaro, F. D., Araújo, H. M., Sierra, D. Aristizabal, Asaadi, J., Attié, D., Aune, S., Awe, C., Ayyad, Y., Baracchini, E., Barbeau, P., Battat, J. B. R., Bell, N. F., Biasuzzi, B., Bignell, L. J., Boehm, C., Bolognino, I., Brunbauer, F. M., Caamaño, M., Cabo, C., Caratelli, D., Carmona, J. M., Castel, J. F., Cebrián, S., Cogollos, C., Collison, D., Costa, E., Dafni, T., Dastgiri, F., Deaconu, C., De Romeri, V., Desch, K., Dho, G., Di Giambattista, F., Díez-Ibáñez, D., D'Imperio, G., Dutta, B., Eldridge, C., Elliott, S. R., Ezeribe, A. C., Fava, A., Felkl, T., Fernández-Domínguez, B., Ribas, E. Ferrer, Flöthner, K. J., Froehlich, M., Galán, J., Galindo, J., García, F., Pascual, J. A. García, Gelli, B. P., Ghrear, M., Giomataris, Y., Gnanvo, K., Gramellini, E., Di Cortona, G. Grilli, Hall-Wilton, R., Harton, J., Hedges, S., Higashino, S., Hill, G., Holanda, P. C., Ikeda, T., Irastorza, I. G., Jackson, P., Janssens, D., Jones, B., Kaminski, J., Katsioulas, I., Kelly, K., Kemmerich, N., Kemp, E., Korandla, H. B., Kraus, H., Lackner, A., Lane, G. J., Lewis, P. M., Lisowska, M., Luzón, G., Lynch, W. A., Maccarrone, G., Mack, K. J., Majewski, P. A., Mano, R. D. P., Margalejo, C., Markoff, D., Marley, T., Marques, D. J. G., Massarczyk, R., Mazzitelli, G., McCabe, C., McKie, L. J., McLean, A. G., McNamara, P. C., Mei, Y., Messina, A., Mills, A. F., Mirallas, H., Miuchi, K., Monteiro, C. M. B., Mosbech, M. R., Muller, H., da Luz, H. Natal, Nakamura, K. D., Natochii, A., Neep, T., Newstead, J. L., Nikolopoulos, K., Obis, L., Oliveri, E., Orlandini, G., de Solórzano, A. Ortiz, von Oy, J., Papaevangelou, T., Pérez, O., Perez-Gonzalez, Y. F., Pfeiffer, D., Phan, N. S., Piacentini, S., Olloqui, E. Picatoste, Pinci, D., Popescu, S., Prajapati, A., Queiroz, F. S., Raaf, J. L., Resnati, F., Ropelewski, L., Roque, R. C., Ruiz-Choliz, E., Rusu, A., Ruz, J., Samarati, J., Santos, E. M., Santos, J. M. F. dos, Sauli, F., Scharenberg, L., Schiffer, T., Schmidt, S., Scholberg, K., Schott, M., Schueler, J., Segui, L., Sekiya, H., Sengupta, D., Slavkovska, Z., Snowden-Ifft, D., Soffitta, P., van Stenis, M., Spooner, N. J. C., Strigari, L., Stuchbery, A. E., Sun, X., Torelli, S., Tilly, E. G., Thomas, A. W., Thorpe, T. N., Urquijo, P., Utrobičić, A., Vahsen, S. E., Veenhof, R., Vogel, J. K., Williams, A. G., Wood, M. H., and Zettlemoyer, J.

Abstract

Recoil imaging entails the detection of spatially resolved ionization tracks generated by particle interactions. This is a highly sought-after capability in many classes of detector, with broad applications across particle and astroparticle physics. However, at low energies, where ionization signatures are small in size, recoil imaging only seems to be a practical goal for micro-pattern gas detectors. This white paper outlines the physics case for recoil imaging, and puts forward a decadal plan to advance towards the directional detection of low-energy recoils with sensitivity and resolution close to fundamental performance limits. The science case covered includes: the discovery of dark matter into the neutrino fog, directional detection of sub-MeV solar neutrinos, the precision study of coherent-elastic neutrino-nucleus scattering, the detection of solar axions, the measurement of the Migdal effect, X-ray polarimetry, and several other applied physics goals. We also outline the R&D programs necessary to test concepts that are crucial to advance detector performance towards their fundamental limit: single primary electron sensitivity with full 3D spatial resolution at the $\sim$100 micron-scale. These advancements include: the use of negative ion drift, electron counting with high-definition electronic readout, time projection chambers with optical readout, and the possibility for nuclear recoil tracking in high-density gases such as argon. We also discuss the readout and electronics systems needed to scale-up such detectors to the ton-scale and beyond., Comment: 77 pages, 20 figures. Submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)

Published
2022

6. Recoil imaging for dark matter, neutrinos, and physics beyond the Standard Model

Author

Ciaran O'Hare, Loomba, D., Altenmuller, K., Alvarez-Pol, H., Amaro, F. D., Araujo, H. M., Aristizabal Sierra, D., Asaadi, J., Attie, D., Aune, S., Awe, C., Ayyad, Y., Baracchini, e, Barbeau, P., Battat, J. B. R., Bell, N. F., Biasuzzi, B., Bignell, L. J., Boehm, C., Bolognino, I., Brunbauer, F. M., Caamano, M., Cabo, C., Caratelli, D., Carmona, J. M., Castel, J. F., Cebrián, S., Cogollos, C., Collison, D., Costa, E., Dafni, T., Dastgiri, F., Deaconu, C., Romeri, V., Desch, K., Dho, G., Di Giambattista, F., Dezibánez, D., D Imperio, G., Dutta, B., Eldridge, C., Elliott, S. R., Ezeribe, A. C., Fava, A., Felkl, T., Fernández-Domnguez, B., Ferrer Ribas, E., Flothner, K. J., Froehlich, M., Galán, J., Galindo, J., Garca, F., Garca Pascual, J. A., Gelli, B. P., Ghrear, M., Giomataris, Y., Gnanvo, K., Gramellini, E., Di Cortona, G. Grilli, Hall-Wilton, R., Harton, J., Hedges, S., Higashino, S., Hill, G., Holanda, P. C., Ikeda, T., Irastorza, I. G., Jackson, P., Janssens, D., Jones, B., Kaminski, J., Katsioulas, I., Kelly, K., Kemmerich, N., Kemp, E., Korandla, H. B., Kraus, H., Lackner, A., Lane, G. J., Lewis, P. M., Lisowska, M., Luzón, G., Lynch, W. A., Maccarrone, G., Mack, K. J., Majewski, P. A., Mano, R. D. P., Margalejo, C., Markoff, D., Marley, T., Marques, D. J. G., Massarczyk, R., Mazzitelli, G., Mccabe, C., Mckie, L. J., Mclean, A. G., Mcnamara, P. C., Mei, Y., Messina, A., Mills, A. F., Mirallas, H., Miuchi, K., Monteiro, C. M. B., Mosbech, M. R., Muller, H., Natal Da Luz, H., Nakamura, K. D., Natochii, A., Neep, T., Newstead, J. L., Nikolopoulos, K., Obis, L., Oliveri, E., Orlandini, G., Ortiz de Solórzano, A., Oy, J., Papaevangelou, T., Pérez, O., Perez-Gonzalez, Y. F., Pfeiffer, D., Phan, N. S., Piacentini, S., Picatoste Olloqui, E., Pinci, D., Popescu, S., Prajapati, A., Queiroz, F. S., Raaf, J. L., Resnati, F., Ropelewski, L., Roque, R. C., Ruiz-Choliz, E., Rusu, A., Ruz, J., Samarati, J., Santos, E. M., Dos Santos, J. M. F., Sauli, F., Scharenberg, L., Schiffer, T., Schmidt, S., Scholberg, K., Schott, M., Schueler, J., Segui, L., Sekiya, H., Sengupta, D., Slavkovska, Z., Snowden-Ifft, D., Soffitta, P., Stenis, M., Spooner, N. J. C., Strigari, L., Stuchbery, A. E., Sun, X., Torelli, S., Tilly, E. G., Thomas, A. W., Thorpe, T. N., Urquijo, P., Utrobicic, A., Vahsen, S. E., Veenhof, R., Vogel, J. K., Williams, A. G., Wood, M. H., and Zettlemoyer, J.

Subjects
Astrophysics and Astronomy, Physics::Instrumentation and Detectors, hep-ex, astro-ph.CO, hep-ph, Detectors and Experimental Techniques, physics.ins-det, Particle Physics - Experiment, Particle Physics - Phenomenology
Abstract

Recoil imaging entails the detection of spatially resolved ionization tracks generated by particle interactions. This is a highly sought-after capability in many classes of detector, with broad applications across particle and astroparticle physics. However, at low energies, where ionization signatures are small in size, recoil imaging only seems to be a practical goal for micro-pattern gas detectors. This white paper outlines the physics case for recoil imaging, and puts forward a decadal plan to advance towards the directional detection of low-energy recoils with sensitivity and resolution close to fundamental performance limits. The science case covered includes: the discovery of dark matter into the neutrino fog, directional detection of sub-MeV solar neutrinos, the precision study of coherent-elastic neutrino-nucleus scattering, the detection of solar axions, the measurement of the Migdal effect, X-ray polarimetry, and several other applied physics goals. We also outline the R&D programs necessary to test concepts that are crucial to advance detector performance towards their fundamental limit: single primary electron sensitivity with full 3D spatial resolution at the $\sim$100 micron-scale. These advancements include: the use of negative ion drift, electron counting with high-definition electronic readout, time projection chambers with optical readout, and the possibility for nuclear recoil tracking in high-density gases such as argon. We also discuss the readout and electronics systems needed to scale-up such detectors to the ton-scale and beyond.

Published
2022

12. Dark matter annihilation in the circumgalactic medium at high redshifts.

Author

Schön, S., Mack, K. J., and Wyithe, J. S. B.

Subjects
*DARK matter, *INTERSTELLAR medium, *GALACTIC redshift, *ENERGY transfer, *SPECTRUM analysis, NEUTRALINOS
Abstract

Annihilating dark matter (DM) models offer promising avenues for future DM detection, in particular via modification of astrophysical signals. However, when modelling such potential signals at high redshift, the emergence of both DM and baryonic structure, as well as the complexities of the energy transfer process, needs to be taken into account. In the following paper, we present a detailed energy deposition code and use this to examine the energy transfer efficiency of annihilating DM at high redshift, including the effects on baryonic structure. We employ the PYTHIA code to model neutralino-like DM candidates and their subsequent annihilation products for a range of masses and annihilation channels. We also compare different density profiles and mass-concentration relations for 105-107M⊙ haloes at redshifts 20 and 40. For these DM halo and particle models, we show radially dependent ionization and heating curves and compare the deposited energy to the haloes' gravitational binding energy. We use the 'filtered' annihilation spectra escaping the halo to calculate the heating of the circumgalactic medium and show that the mass of the minimal star-forming object is increased by a factor of 2-3 at redshift 20 and 4-5 at redshift 40 for some DM models. [ABSTRACT FROM AUTHOR]

Published
2018
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15. The Cosmic Dawn and Epoch of Reionisation with SKA

Author

Koopmans, Leon, primary, Pritchard, J, additional, Mellema, G, additional, Aguirre, J, additional, Ahn, K, additional, Barkana, R, additional, van Bemmel, I, additional, Bernardi, G, additional, Bonaldi, A, additional, Briggs, F, additional, de Bruyn, A. G., additional, Chang, T. C., additional, Chapman, E, additional, Chen, X, additional, Courty, B, additional, Dayal, P., additional, Ferrara, A., additional, Fialkov, A., additional, Fiore, F, additional, Ichiki, K., additional, Illiev, I. T., additional, Inoue, S, additional, Jelic, V, additional, Jones, M, additional, Lazio, J, additional, Maio, U, additional, Majumdar, S, additional, Mack, K. J., additional, Mesinger, A., additional, Morales, M F., additional, Parsons, A., additional, Pen, U.L., additional, Santos, M, additional, Schneider, R, additional, Semelin, B, additional, de Souza, R S, additional, Subrahmanyan, R, additional, Takeuchi, T, additional, Vedantham, H, additional, Wagg, J, additional, Webster, R, additional, Wyithe, S, additional, Datta, Kanan Kumar, additional, and Trott, C., additional

Published
2015
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20. MHD flow and heat transfer in a rectangular duct

Author

Barleon, L., Burr, U., Frank, M., Stieglitz, R., and Mack, K. J.

Subjects
ddc:620, Engineering & allied operations
Abstract

MHD Strömung und Wärmeübergang in einem Rechteckkanal Lediglich eine profunde Kenntnis des Wärmeübertragungsverhaltens laminarer und turbulenter magnetohydrodynamischer (MHD) Strömungen erlaubt eine adäquate Auslegung von Wärmeübertragern, zum Beispiel von Flüssigmetallblankets, oder eine Steuerung industrieller Verfahren durch den Einsatz von MHD Effekten. In diesem Bericht wird die experimentelle und numerische Untersuchung einer MHD-Strömung in einem Rechteckkanal mit elektrisch leitenden Wänden vorgestellt. Ein äußeres konstantes Magnetfeld B steht senkrecht auf der Kanalachse und ist ebenfalls senkrecht zum Wärmestrom , der von einem Strahlungsheizer erzeugt wird. Im Kanal werden sowohl integrale Größen wie der Druckverlust und die Nusselt-Zahl aber auch lokale Größen, zum Beispiel die Temperatur an der Fluid-Wand-Grenzfläche, die Geschwindigkeit und die lokale Temperatur ermittelt. Der untersuchte Parameterbereich umfaßt: Hartmann-Zahlen 0£ M£ 5000, Reynolds-Zahlen 0£ Re£ 1.3.105 und Peclet-Zahlen 0£ Pe£ 2900 . Der gemessene Druckverlust stimmt mit der analytischen Lösung für eine zweidimensionale MHD-Strömung in nahezu dem gesamten untersuchten Parameterbereich überein. Lediglich für Hartmann-Zahlen M£ 350 und Re³ 7.104 wird ein höherer Druckverlust ermittelt. Beim Überschreiten einer kritischen Reynoldszahl Recrit von Recrit=100.M entspricht der MHD-Druckverlust dem einer turbulenten hydrodynamischen Rohrströmung. Die Temperatur- und Geschwindigkeitsverteilung im Kanal, die mit einer kombinierten Temperatur- und Geschwindigkeitsmeßsonde (TEMPO) ermittelt wurde, stimmt mit den berechneten Werten für eine laminare MHD-Strömung überein. Die Nusselt-Zahl an der Wand ist bei MHD-Strömungen aufgrund der wandnahen Geschwindigkeitsüberhöhungen (den sogenannten Seitenwandjets), die sich an Wänden parallel zum Magnetfeld ausbilden und direkt dem Wärmestrom ausgesetzt ist, um ca. 30% größer als in einer hydrodynamischen Strömung. Bei großen M und sehr großen Re entspricht der Wärmeübergang der turbulenten MHD Strömung dem Wärmeübergang wie er auch in einer laminaren Strömung ermittelt wird. Der Grund dafür ist, daß die thermische Grenzschicht sich noch im Bereich der viskosen laminaren Grenzschicht befindet und somit leistet lediglich die molekulare Wärmeleitung einen Beitrag zur Wärmeübertragung. Bei bestimmten Parameterkonstellationen oder bei hinreichend langen Kanälen wächst die Grenzschicht in den Bereich der turbulenten Seitenwandschichten hinein. Durch den turbulenten Quertransport des Fluids wird der Wärmeübergang gesteigert. Die Wärmeübertragungsverbesserung kann um den Faktor 2 höher sein als bei einer laminaren MHD-Strömung.

Published
1998
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39. The cosmic dawn and epoch of reionization with the square kilometre array

Author

Koopmans, L. V. E., Pritchard, J., Mellema, G., Abdalla, F., Aguirre, J., Ahn, K., Barkana, R., Bemmel, I., Bernardi, G., Bonaldi, A., Briggs, F., Bruyn, A. G., Chang, T. C., Chapman, E., Chen, X., Ciardi, B., Datta, K. K., Dayal, P., Ferrara, A., Fialkov, A., Fiore, F., Ichiki, K., Illiev, I. T., Inoue, S., Jelić, V., Jones, M., Lazio, J., Maio, U., Suman Majumdar, Mack, K. J., Mesinger, A., Morales, M. F., Parsons, A., Pen, U. -L, Santos, M., Schneider, R., Semelin, B., Souza, R. S., Subrahmanyan, R., Takeuchi, T., Trott, C., Vedantham, H., Wagg, J., Webster, R., and Wyithe, S.

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Concerted effort is currently ongoing to open up the Epoch of Reionization (EoR) ($z\sim$15-6) for studies with IR and radio telescopes. Whereas IR detections have been made of sources (Lyman-$\alpha$ emitters, quasars and drop-outs) in this redshift regime in relatively small fields of view, no direct detection of neutral hydrogen, via the redshifted 21-cm line, has yet been established. Such a direct detection is expected in the coming years, with ongoing surveys, and could open up the entire universe from $z\sim$6-200 for astrophysical and cosmological studies, opening not only the EoR, but also its preceding Cosmic Dawn ($z\sim$30-15) and possibly even the later phases of the Dark Ages ($z\sim$200-30). All currently ongoing experiments attempt statistical detections of the 21-cm signal during the EoR, with limited signal-to-noise. Direct imaging, except maybe on the largest (degree) scales at lower redshifts, as well as higher redshifts will remain out of reach. The Square Kilometre Array(SKA) will revolutionize the field, allowing direct imaging of neutral hydrogen from scales of arc-minutes to degrees over most of the redshift range $z\sim$6-28 with SKA1-LOW, and possibly even higher redshifts with the SKA2-LOW. In this SKA will be unique, and in parallel provide enormous potential of synergy with other upcoming facilities (e.g. JWST). In this chapter we summarize the physics of 21-cm emission, the different phases the universe is thought to go through, and the observables that the SKA can probe, referring where needed to detailed chapters in this volume (Abridged)., Comment: Accepted for publication in the SKA Science Book 'Advancing Astrophysics with the Square Kilometre Array', to appear in 2015. PoS(AASKA14)001

40. CYGNUS: Feasibility of a nuclear recoil observatory with directional sensitivity to dark matter and neutrinos

Author

Vahsen, S. E., Ciaran O'Hare, Lynch, W. A., Spooner, N. J. C., Baracchini, E., Barbeau, P., Battat, J. B. R., Crow, B., Deaconu, C., Eldridge, C., Ezeribe, A. C., Ghrear, M., Loomba, D., Mack, K. J., Miuchi, K., Mouton, F. M., Phan, N. S., Scholberg, K., and Thorpe, T. N.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment (hep-ex), Physics - Instrumentation and Detectors, Cosmology and Nongalactic Astrophysics (astro-ph.CO), High Energy Physics - Phenomenology (hep-ph), Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Experiment
Abstract

Now that conventional weakly interacting massive particle (WIMP) dark matter searches are approaching the neutrino floor, there has been a resurgence of interest in detectors with sensitivity to nuclear recoil directions. A large-scale directional detector is attractive in that it would have sensitivity below the neutrino floor, be capable of unambiguously establishing the galactic origin of a purported dark matter signal, and could serve a dual purpose as a neutrino observatory. We present the first detailed analysis of a 1000 m$^3$-scale detector capable of measuring a directional nuclear recoil signal at low energies. We propose a modular and multi-site observatory consisting of time projection chambers (TPCs) filled with helium and SF$_6$ at atmospheric pressure. Depending on the TPC readout technology, 10-20 helium recoils above 6 keVr or only 3-4 recoils above 20 keVr would suffice to distinguish a 10 GeV WIMP signal from the solar neutrino background. High-resolution charge readout also enables powerful electron background rejection capabilities well below 10 keV. We detail background and site requirements at the 1000 m$^3$-scale, and identify materials that require improved radiopurity. The final experiment, which we name CYGNUS-1000, will be able to observe 10-40 neutrinos from the Sun, depending on the final energy threshold. With the same exposure, the sensitivity to spin independent cross sections will extend into presently unexplored sub-10 GeV parameter space. For spin dependent interactions, already a 10 m$^3$-scale experiment could compete with upcoming generation-two detectors, but CYGNUS-1000 would improve upon this considerably. Larger volumes would bring sensitivity to neutrinos from an even wider range of sources, including galactic supernovae, nuclear reactors, and geological processes., Comment: 64 pages, 34 figures

44. Phosphorylation, CREB, and Mental Retardation.

Author

Todd PK and Mack KJ

Subjects
Humans, Intellectual Disability metabolism, Phosphorylation, Protein Serine-Threonine Kinases metabolism, Cyclic AMP Response Element-Binding Protein metabolism, Intellectual Disability genetics, Ribosomal Protein S6 Kinases, 90-kDa
Published
2001
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45. Invited review: Intermittent hypoxia and respiratory plasticity.

Author

Mitchell GS, Baker TL, Nanda SA, Fuller DD, Zabka AG, Hodgeman BA, Bavis RW, Mack KJ, and Olson EB Jr

Subjects
Animals, Humans, Respiratory System innervation, Hypoxia physiopathology, Neuronal Plasticity physiology, Respiratory Physiological Phenomena
Abstract

Intermittent hypoxia elicits long-term facilitation (LTF), a persistent augmentation (hours) of respiratory motor output. Considerable recent progress has been made toward an understanding of the mechanisms and manifestations of this potentially important model of respiratory plasticity. LTF is elicited by intermittent but not sustained hypoxia, indicating profound pattern sensitivity in its underlying mechanism. During intermittent hypoxia, episodic spinal serotonin receptor activation initiates cell signaling events, increasing spinal protein synthesis. One associated protein is brain-derived neurotrophic factor, a neurotrophin implicated in several forms of synaptic plasticity. Our working hypothesis is that increased brain-derived neurotrophic factor enhances glutamatergic synaptic currents in phrenic motoneurons, increasing their responsiveness to bulbospinal inspiratory inputs. LTF is heterogeneous among respiratory outputs, differs among experimental preparations, and is influenced by age, gender, and genetics. Furthermore, LTF is enhanced following chronic intermittent hypoxia, indicating a degree of metaplasticity. Although the physiological relevance of LTF remains unclear, it may reflect a general mechanism whereby intermittent serotonin receptor activation elicits respiratory plasticity, adapting system performance to the ever-changing requirements of life.

Published
2001
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46. Sensory stimulation increases cortical expression of the fragile X mental retardation protein in vivo.

Author

Todd PK and Mack KJ

Subjects
Animals, Calcineurin metabolism, Fragile X Mental Retardation Protein, Kainic Acid, Male, Rats, Rats, Sprague-Dawley, Seizures chemically induced, Somatosensory Cortex drug effects, Fragile X Syndrome metabolism, Intellectual Disability metabolism, Nerve Tissue Proteins biosynthesis, RNA-Binding Proteins biosynthesis, Sensory Thresholds physiology
Abstract

Fragile X syndrome is a common cause of mental retardation that results from the absence of the fragile X mental retardation protein (FMRP), an RNA binding protein whose function remains unclear. Recent in vitro work has demonstrated that the protein is translated near the synapse in an activity dependent manner [33]. We therefore asked whether expression of FMRP might be altered by neuronal activity in vivo. Using immunoblots of different sub-cellular fractions of the rat somatosensory cortex, we show that the levels of FMRP increase significantly following unilateral whisker stimulation, a model of experience dependent plasticity. This increase is greatest between 2 and 8 h after the stimulus and is seen in both a synaptosomal fraction as well as a sub-cellular fraction enriched for polyribosomal complexes. In contrast, detectable levels of FMRP within the somatosensory cortex show either a decrease or no change after a kainic acid induced seizure compared to water treated controls. Our findings demonstrate that FMRP expression levels are modulated in vivo in response to neuronal activity and suggest a role for FMRP in activity dependent plasticity.

Published
2000
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47. Seizures and sensory stimulation result in different patterns of brain derived neurotrophic factor protein expression in the barrel cortex and hippocampus.

Author

Nanda SA and Mack KJ

Subjects
Animals, Brain-Derived Neurotrophic Factor analysis, Brain-Derived Neurotrophic Factor metabolism, Convulsants, Epilepsy chemically induced, Excitatory Amino Acid Agonists, Gene Expression physiology, Hippocampus chemistry, Hippocampus metabolism, Kainic Acid, Male, Neuronal Plasticity physiology, Pentylenetetrazole, Physical Stimulation, RNA, Messenger analysis, Rats, Rats, Sprague-Dawley, Seizures chemically induced, Seizures physiopathology, Somatosensory Cortex chemistry, Somatosensory Cortex metabolism, Vibrissae innervation, Vibrissae physiology, Brain-Derived Neurotrophic Factor genetics, Epilepsy physiopathology, Hippocampus physiopathology, Somatosensory Cortex physiopathology, Touch physiology
Abstract

Brain-derived neurotrophic factor (BDNF) is important for the development and trophic support of neurons, and may be involved in controlling axonal sprouting and synaptic plasticity. In order to investigate the activity-dependent regulation of the BDNF gene, BDNF expression was examined within the rat somatosensory cortex (SSC) and hippocampus following vibrissae stimulation, kainic acid induced seizure, and pentylenetetrazol (PTZ) induced seizure. The specific goals of this study were to determine the time course and magnitude of BDNF's activity-dependent expression, and to compare the expression patterns of three commonly used neuronal activation paradigms. Our results demonstrate three novel observations. First, the patterns of BDNF protein expression are dependent upon the neuronal stimulation model used. Both unilateral whisker stimulation (a model of experience dependent plasticity) and kainic acid induced seizure were able to increase the levels of BDNF protein within the SSC and hippocampus. In contrast, PTZ induced seizure did not increase BDNF protein levels in either tissue. Second, there is a dissociation between BDNF mRNA and protein levels following PTZ induced seizure. PTZ seizures resulted in strong increases of BDNF mRNA levels without corresponding increases of the protein. Finally, whisker stimulation resulted in an unexpected increase in BDNF mRNA and protein levels within the hippocampus. These results suggest specific types of neuronal activity can regulate gene expression differently. Furthermore, temporal and spatial differences between the expression of BDNF protein and mRNA levels suggest that the BDNF gene is regulated at the level of translation as well as transcription.

Published
2000
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48. Multiple promoters direct stimulus and temporal specific expression of brain-derived neurotrophic factor in the somatosensory cortex.

Author

Nanda S and Mack KJ

Subjects
Animals, Brain-Derived Neurotrophic Factor biosynthesis, Nerve Tissue Proteins biosynthesis, RNA, Messenger biosynthesis, Rats, Reverse Transcriptase Polymerase Chain Reaction, Seizures chemically induced, Seizures metabolism, Time Factors, Transcription, Genetic, Vibrissae physiology, Brain-Derived Neurotrophic Factor genetics, Gene Expression Regulation, Nerve Tissue Proteins genetics, Promoter Regions, Genetic, Somatosensory Cortex metabolism
Abstract

Neuronal activity rapidly induces expression of brain-derived neurotrophic factor (BDNF) in the adult rat cortex. The rat BDNF gene has four differentially regulated promoters, each of which produce an mRNA containing a unique 5' exon (I-IV) and a common 3' exon (V) that encodes the mature BDNF protein. The present study used an exon-specific RT-PCR analysis to determine the time course of the induction from both seizures and whisker stimulation. Our data show that specific promoters are utilized at different stages of the activity-dependent induction of the BDNF gene. Furthermore, the data show a differential utilization of the four promoters following a specific stimulus., (Copyright 1998 Elsevier Science B.V.)

Published
1998
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49. Cerebrospinal fluid free choline in movement disorders of paediatric onset.

Author

Pranzatelli MR, Hanin I, Tate E, Kindel G, Bergin A, Brown CM, Habersang P, Habersang R, Mack KJ, Rosenbaum B, Selby KA, and Vasconcellos M

Subjects
Acetylcholine cerebrospinal fluid, Adrenocorticotropic Hormone therapeutic use, Adult, Child, Child, Preschool, Chromatography, High Pressure Liquid methods, Disease Progression, Epilepsies, Myoclonic cerebrospinal fluid, Epilepsies, Myoclonic complications, Female, Humans, Male, Movement Disorders complications, Movement Disorders drug therapy, Phospholipids metabolism, Choline cerebrospinal fluid, Movement Disorders cerebrospinal fluid
Abstract

We measured free choline in cerebrospinal fluid (CSF) of 78 patients with movement disorders of paediatric onset and various controls as a putative index of central phospholipid metabolism. Most of the disorders studied were myoclonic disorders, such as progressive myoclonus epilepsy, the opsoclonus-myoclonus syndrome, and essential myoclonus, but other movement disorders, interictal seizure disorders, and different neurological and nonneurological disorders were also included. There were no significant differences in CSF choline concentrations in myoclonic disorders or other movement disorders compared with controls. The CSF choline levels were lowest in children with seizure disorders including progressive myoclonus epilepsy. In progressive myoclonus epilepsy, the CSF choline values resembled other epileptic disorders rather than other myoclonic disorders. When all the data were analysed collectively, no significant relation of CSF choline was found to patient age, gender, aliquot of CSF measured, or the length of time the sample was stored at -70 degrees C. Separate analyses of data from children and adults showed a trend toward a biphasic relation between patient age and CSF choline which could be pursued in developmental studies of normal subjects. Reduced CSF choline may indicate increased choline incorporation into brain phospholipids, disturbances of choline metabolism, decreased choline release, or non-neural factors.

Published
1998
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50. Cortical NMDAR-1 gene expression is rapidly upregulated after seizure.

Author

Jensen PJ, Millan N, and Mack KJ

Subjects
Animals, Gene Expression, Male, Rats, Rats, Sprague-Dawley, Time Factors, Cerebral Cortex metabolism, Cerebral Cortex physiopathology, Receptors, N-Methyl-D-Aspartate metabolism, Seizures metabolism, Seizures physiopathology, Up-Regulation physiology
Abstract

The promoter region of the NMDAR-1 receptor has a cis-regulatory element that is capable of binding to the NGFI-A family of transcription factors. Based on this observation, we hypothesized that situations that cause a change in NGFI-A levels would result in a change in NMDAR-1 expression. In these studies, we have demonstrated that a seizure results in a rapid significant increase in NMDAR-1 mRNA and protein expression, at a time when NGFI-A protein levels are expected to be elevated. Our results indicate that control of NMDAR-1 expression is stimulus, time and tissue dependent.

Published
1997
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