Search Results - "Udaya Shankar, N."

On the detection of a cosmic dawn signal in the radio background by Singh, Saurabh, Nambissan T., Jishnu, Subrahmanyan, Ravi, Udaya Shankar, N., Girish, B. S., Raghunathan, A., Somashekar, R., Srivani, K. S., Sathyanarayana Rao, Mayuri

“…The astrophysics of the cosmic dawn, when star formation commenced in the first collapsed objects, is predicted to be revealed by spectral and spatial…”
Get full text

Improving the Epoch of Reionization Power Spectrum Results from Murchison Widefield Array Season 1 Observations by Barry, N., Wilensky, M., Trott, C. M., Pindor, B., Beardsley, A. P., Hazelton, B. J., Sullivan, I. S., Morales, M. F., Pober, J. C., Line, J., Greig, B., Byrne, R., Lanman, A., Li, W., Jordan, C. H., Joseph, R. C., McKinley, B., Rahimi, M., Yoshiura, S., Bowman, J. D., Gaensler, B. M., Hewitt, J. N., Jacobs, D. C., Mitchell, D. A., Udaya Shankar, N., Sethi, S. K., Subrahmanyan, R., Tingay, S. J., Webster, R. L., Wyithe, J. S. B.

“…Measurements of 21 cm Epoch of Reionization (EoR) structure are subject to systematics originating from both the analysis and the observation conditions. Using…”
Get full text

SARAS 2 Constraints on Global 21 cm Signals from the Epoch of Reionization by Singh, Saurabh, Subrahmanyan, Ravi, Shankar, N. Udaya, Rao, Mayuri Sathyanarayana, Fialkov, Anastasia, Cohen, Aviad, Barkana, Rennan, Girish, B. S., Raghunathan, A., Somashekar, R., Srivani, K. S.

“…Abstract Spectral distortions in the cosmic microwave background over the 40–200 MHz band are imprinted by neutral hydrogen in the intergalactic medium prior…”
Get full text

GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey – I. A low-frequency extragalactic catalogue by Hurley-Walker, N, Callingham, J R, Hancock, P J, Franzen, T M O, Hindson, L, Kapinska, A D, Morgan, J, Offringa, A R, Wayth, R B, Wu, C, Zheng, Q, Murphy, T, Bell, M E, Dwarakanath, K S, Gaensler, B M, Johnston-Hollitt, M, Lenc, E, Procopio, P, Staveley-Smith, L, Ekers, R, Bowman, J D, Briggs, F, Cappallo, R J, Deshpande, A A, Greenhill, L, Hazelton, B J, Kaplan, D L, Lonsdale, C J, McWhirter, S R, Mitchell, D A, Morales, M F, Morgan, E, Oberoi, D, Ord, S M, Prabu, T, Shankar, N Udaya, Srivani, K S, Subrahmanyan, R, Tingay, S J, Webster, R L, Williams, A, Williams, C L

“…Abstract Using the Murchison Widefield Array (MWA), the low-frequency Square Kilometre Array precursor located in Western Australia, we have completed the…”
Get full text

Limits on Fast Radio Bursts and other transient sources at 182 MHz using the Murchison Widefield Array by Rowlinson, A., Bell, M. E., Murphy, T., Trott, C. M., Hurley-Walker, N., Johnston, S., Tingay, S. J., Kaplan, D. L., Carbone, D., Hancock, P. J., Feng, L., Offringa, A. R., Bernardi, G., Bowman, J. D., Briggs, F., Cappallo, R. J., Deshpande, A. A., Gaensler, B. M., Greenhill, L. J., Hazelton, B. J., Johnston-Hollitt, M., Lonsdale, C. J., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Oberoi, D., Ord, S. M., Prabu, T., Udaya Shankar, N., Srivani, K. S., Subrahmanyan, R., Wayth, R. B., Webster, R. L., Williams, A., Williams, C. L.

“…We present a survey for transient and variable sources, on time-scales from 28 s to ∼1 yr, using the Murchison Widefield Array (MWA) at 182 MHz. Down to a…”
Get full text

Comparing Redundant and Sky-model-based Interferometric Calibration: A First Look with Phase II of the MWA by Li, W., Pober, J. C., Hazelton, B. J., Barry, N., Morales, M. F., Sullivan, I., Parsons, A. R., Ali, Z. S., Dillon, J. S., Beardsley, A. P., Bowman, J. D., Briggs, F., Byrne, R., Carroll, P., Crosse, B., Emrich, D., Ewall-Wice, A., Feng, L., Franzen, T. M. O., Hewitt, J. N., Horsley, L., Jacobs, D. C., Johnston-Hollitt, M., Jordan, C., Joseph, R. C., Kaplan, D. L., Kenney, D., Kim, H., Kittiwisit, P., Lanman, A., Line, J., McKinley, B., Mitchell, D. A., Murray, S., Neben, A., Offringa, A. R., Pallot, D., Paul, S., Pindor, B., Procopio, P., Rahimi, M., Riding, J., Sethi, S. K., Udaya Shankar, N., Steele, K., Subrahmanian, R., Tegmark, M., Thyagarajan, N., Tingay, S. J., Trott, C., Walker, M., Wayth, R. B., Webster, R. L., Williams, A., Wu, C., Wyithe, S.

“…Interferometric arrays seeking to measure the 21 cm signal from the epoch of reionization (EOR) must contend with overwhelmingly bright emission from…”
Get full text

SARAS: a precision system for measurement of the cosmic radio background and signatures from the epoch of reionization by Patra, Nipanjana, Subrahmanyan, Ravi, Raghunathan, A., Udaya Shankar, N.

“…SARAS is a correlation spectrometer purpose designed for precision measurements of the cosmic radio background and faint features in the sky spectrum at long…”
Get full text

PRATUSH experiment concept and design overview by Sathyanarayana Rao, Mayuri, Singh, Saurabh, K.S., Srivani, B.S., Girish, Sathish, Keerthipriya, R., Somashekar, Agaram, Raghunathan, K., Kavitha, Vishwapriya, Gautam, Anand, Ashish, N., Udaya Shankar, S., Seetha

“…PRATUSH – Probing ReionizATion of the Universe using Signal from Hydrogen – is a proposed cosmology experiment to detect the global red-shifted 21-cm signal…”
Get full text

A Wideband Resistive Beam-Splitter Screen by Mahesh, Nivedita, Subrahmanyan, Ravi, Shankar, N. Udaya, Raghunathan, Agaram

“…We present the design, construction, and measurements of the electromagnetic performance of a wideband space beam splitter. The beam splitter is a sheet in…”
Get full text

A multifrequency radio continuum study of the Magellanic Clouds – I. Overall structure and star formation rates by For, B-Q, Staveley-Smith, L, Hurley-Walker, N, Franzen, T, Kapińska, A D, Filipović, M D, Collier, J D, Wu, C, Grieve, K, Callingham, J R, Bell, M E, Bernardi, G, Bowman, J D, Briggs, F, Cappallo, R J, Deshpande, A A, Dwarakanath, K S, Gaensler, B M, Greenhill, L J, Hancock, P, Hazelton, B J, Hindson, L, Johnston-Hollitt, M, Kaplan, D L, Lenc, E, Lonsdale, C J, McKinley, B, McWhirter, S R, Mitchell, D A, Morales, M F, Morgan, E, Morgan, J, Oberoi, D, Offringa, A, Ord, S M, Prabu, T, Procopio, P, Shankar, N Udaya, Srivani, K S, Subrahmanyan, R, Tingay, S J, Wayth, R B, Webster, R L, Williams, A, Williams, C L, Zheng, Q

Get full text

Time-domain and spectral properties of pulsars at 154 MHz by Bell, M E, Murphy, Tara, Johnston, S, Kaplan, D L, Croft, S, Hancock, P, Callingham, J R, Zic, A, Dobie, D, Swiggum, J K, Rowlinson, A, Hurley-Walker, N, Offringa, A R, Bernardi, G, Bowman, J D, Briggs, F, Cappallo, R J, Deshpande, A A, Gaensler, B M, Greenhill, L J, Hazelton, B J, Johnston-Hollitt, M, Lonsdale, C J, McWhirter, S R, Mitchell, D A, Morales, M F, Morgan, E, Oberoi, D, Ord, S M, Prabu, T, Shankar, N Udaya, Srivani, K S, Subrahmanyan, R, Tingay, S J, Wayth, R B, Webster, R L, Williams, A, Williams, C L

“…We present 154 MHz Murchison Widefield Array imaging observations and variability information for a sample of pulsars. Over the declination range -80... < …”
Get full text

SARAS 3 CD/EoR radiometer: design and performance of the receiver by T., Jishnu Nambissan, Subrahmanyan, Ravi, Somashekar, R., Shankar, N. Udaya, Singh, Saurabh, Raghunathan, A., Girish, B. S., Srivani, K. S., Rao, Mayuri Sathyanarayana

“…SARAS is an ongoing experiment aiming to detect the redshifted global 21-cm signal expected from Cosmic Dawn (CD) and the Epoch of Reionization (EoR). Standard…”
Get full text

Limits on low-frequency radio emission from southern exoplanets with the Murchison Widefield Array by Murphy, Tara, Bell, Martin E, Kaplan, David L, Gaensler, B M, Offringa, Andre R, Lenc, Emil, Hurley-Walker, Natasha, Bernardi, G, Bowman, J D, Briggs, F, Cappallo, R J, Corey, B E, Deshpande, A A, Emrich, D, Goeke, R, Greenhill, L J, Hazelton, B J, Hewitt, J N, Johnston-Hollitt, M, Kasper, J C, Kratzenberg, E, Lonsdale, C J, Lynch, M J, McWhirter, S R, Mitchell, D A, Morales, M F, Morgan, E, Oberoi, D, Ord, S M, Prabu, T, Rogers, A E E, Roshi, D A, Shankar, N Udaya, Srivani, K S, Subrahmanyan, R, Tingay, S J, Waterson, M, Wayth, R B, Webster, R L, Whitney, A R, Williams, A, Williams, C L

“…We present the results of a survey for low-frequency radio emission from 17 known exoplanetary systems with the Murchison Widefield Array. This sample includes…”
Get full text

The EoR sensitivity of the Murchison Widefield Array by Beardsley, A. P., Hazelton, B. J., Morales, M. F., Arcus, W., Barnes, D., Bernardi, G., Bowman, J. D., Briggs, F. H., Bunton, J. D., Cappallo, R. J., Corey, B. E., Deshpande, A., deSouza, L., Emrich, D., Gaensler, B. M., Goeke, R., Greenhill, L. J., Herne, D., Hewitt, J. N., Johnston-Hollitt, M., Kaplan, D. L., Kasper, J. C., Kincaid, B. B., Koenig, R., Kratzenberg, E., Lonsdale, C. J., Lynch, M. J., McWhirter, S. R., Mitchell, D. A., Morgan, E., Oberoi, D., Ord, S. M., Pathikulangara, J., Prabu, T., Remillard, R. A., Rogers, A. E. E., Roshi, A., Salah, J. E., Sault, R. J., Udaya, Shankar N., Srivani, K. S., Stevens, J., Subrahmanyan, R., Tingay, S. J., Wayth, R. B., Waterson, M., Webster, R. L., Whitney, A. R., Williams, A., Williams, C. L., Wyithe, J. S. B.

“…Using the final 128 antenna locations of the Murchison Widefield Array (MWA), we calculate its sensitivity to the epoch of reionization (EoR) power spectrum of…”
Get full text

IMAGING THE EPOCH OF REIONIZATION: LIMITATIONS FROM FOREGROUND CONFUSION AND IMAGING ALGORITHMS by Vedantham, Harish, Udaya Shankar, N., Subrahmanyan, Ravi

“…Tomography of redshifted 21 cm transition from neutral hydrogen using Fourier synthesis telescopes is a promising tool to study the Epoch of Reionization…”
Get full text

Sources of major ions and processes affecting the geochemical and isotopic signatures of subsurface waters along a tropical river, Southwestern India by Gurumurthy, G. P, Balakrishna, K, Tripti, M, Riotte, Jean, Audry, Stéphane, Braun, Jean-Jacques, Lambs, Luc, Udaya Shankar, H. N

“…Systematic monitoring of subsurface hydrogeochemistry has been carried out for a period of one year in a humid tropical region along the Nethravati–Gurupur…”
Get full text

Quantifying ionospheric effects on time-domain astrophysics with the Murchison Widefield Array by Loi, Shyeh Tjing, Murphy, Tara, Bell, Martin E., Kaplan, David L., Lenc, Emil, Offringa, André R., Hurley-Walker, Natasha, Bernardi, G., Bowman, J. D., Briggs, F., Cappallo, R. J., Corey, B. E., Deshpande, A. A., Emrich, D., Gaensler, B. M., Goeke, R., Greenhill, L. J., Hazelton, B. J., Johnston-Hollitt, M., Kasper, J. C., Kratzenberg, E., Lonsdale, C. J., Lynch, M. J., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Oberoi, D., Ord, S. M., Prabu, T., Rogers, A. E. E., Roshi, A., Shankar, N. Udaya, Srivani, K. S., Subrahmanyan, R., Tingay, S. J., Waterson, M., Wayth, R. B., Webster, R. L., Whitney, A. R., Williams, A., Williams, C. L.

“…Refraction and diffraction of incoming radio waves by the ionosphere induce time variability in the angular positions, peak amplitudes and shapes of radio…”
Get full text

Geochemical behaviour of dissolved trace elements in a monsoon-dominated tropical river basin, Southwestern India by Gurumurthy, G. P, Balakrishna, K, Tripti, M, Audry, Stéphane, Riotte, Jean, Braun, J. J, Udaya Shankar, H. N

“…The study presents a 3-year time series data on dissolved trace elements and rare earth elements (REEs) in a monsoon-dominated river basin, the Nethravati…”
Get full text

Radio recombination lines from the largest bound atoms in space by Stepkin, S. V., Konovalenko, A. A., Kantharia, N. G., Udaya Shankar, N.

“…In this paper, we report the detection of a series of radio recombination lines (RRLs) in absorption near 26 MHz arising from the largest bound carbon atoms…”
Get full text

Modeling the Radio Foreground for Detection of CMB Spectral Distortions from the Cosmic Dawn and the Epoch of Reionization by Sathyanarayana Rao, Mayuri, Subrahmanyan, Ravi, Shankar, N Udaya, Chluba, Jens

“…Cosmic baryon evolution during the Cosmic Dawn and Reionization results in redshifted 21-cm spectral distortions in the cosmic microwave background (CMB)…”
Get full text