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1. Navigating the nano-world future: Harnessing cellulose nanocrystals from green sources for sustainable innovation

Author

Felix Sahayaraj Arockiasamy, Bharathi Manoharan, Vivek Mariappan Santhi, K. Prakalathan, Diwahar Periasamy, Aravind Dhandapani, Varagunapandiyan Natarajan, Senthilkumar Krishnasamy, Senthil Muthu Kumar Thiagamani, and R.A. Ilyas

Subjects
Cellulose nanocrystals, Extraction, Characterization, Biocompatibility, Renewable energy, Nanotechnology, Science (General), Q1-390, Social sciences (General), H1-99
Abstract

Cellulose nanocrystals (CNCs) are a class of materials that have received significant attention in recent years due to their unique properties and potential applications. CNCs are extracted from plant fibers and possess high strength, stiffness, and biocompatibility, making them attractive materials for use in various fields such as biomedical engineering, renewable energy, and nanotechnology. This provides an in-depth discussion of the extraction, characterization, and promising applications of CNCs. Furthermore, it discusses the sources of CNCs and the methods used for their extraction as well as the common techniques used to characterize their properties. This work also highlights various applications of CNCs and their advantages over other materials. The challenges associated with the use of CNCs and the current research efforts to address these challenges were analyzed. In addition, the potential future directions and applications for CNCs were discussed. This review article aims to provide a comprehensive understanding of CNCs and their potential as versatile and sustainable materials.

Published
2025
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3. List of contributors

Author

Agarwal, Neha, primary, Agrawal, Komal, additional, Anand, Shreya, additional, Arun, J., additional, Babu, S. Abinesh, additional, Bagaria, Ashima, additional, Baghmare, Pawan, additional, Baitharu, Iswar, additional, Bhandari, Prashasti, additional, Bikiaris, Dimitrios N., additional, Chand, Khem, additional, Choudhary, Sangeeta, additional, Dawn, S.S., additional, Dwaraka, S.J. Bala, additional, Evgenidou, Eleni, additional, Ganesh, Sanjeev K., additional, Geed, Sachin Rameshrao, additional, Ghosh, Sougata, additional, Gkika, Despina A., additional, Gulia, Jyoti, additional, Hemalatha, M., additional, Kalavrouziotis, Ioannis K., additional, Kandasamy, Senthilkumar, additional, Karuriya, Silisti, additional, Katre, Shikha, additional, Kokkinos, Petros, additional, Krishnan, Suresh Kumar, additional, Kumar, Anil, additional, Kumar, Navneet, additional, Kumar, S. Sanjay, additional, Kumar, Sushil, additional, Kyzas, George Z., additional, Lambropoulou, Dimitra A., additional, Lath, Amit, additional, Mahmoud, Yehia A.-G., additional, Marak, Salviush Chingku S., additional, Mitropoulos, Athanasios C., additional, Mohanasrinivasan, V., additional, Murugesan, Sibiraj, additional, Muthulingam, Seenuvasan, additional, Nair, Sreelakshmi R., additional, Nandakumar, N. Pooja, additional, Naveenkumar, M., additional, Nirmala, N., additional, Padmanabhan, Padmini, additional, Priyadharsini, P., additional, Rajadurai, Vijayalakshmi, additional, Rani, Yashika, additional, Rathee, Jitender, additional, Sahoo, Sawan Kumar, additional, Sahu, Ashish Kumar, additional, Santal, Anita Rani, additional, Santhi, Vivek Mariappan, additional, Santhosh, A., additional, Sarkar, Bishwarup, additional, Saxena, Gaurav, additional, Selvanatrajan, Nagul Dev, additional, Sharma, Jitendra Kumar, additional, Singh, Nater Pal, additional, Singh, Neetu, additional, Solanki, Vijendra Singh, additional, Soni, Kanchan, additional, Sreerenjini, R., additional, Srivastava, Amrita, additional, Subathra, M., additional, Subathra Devi, C., additional, Subbiah, Kavitha, additional, Subramanian, Kalidass, additional, Thakur, Kamlesh, additional, Thakur, Vishal, additional, Thongmee, Sirikanjana, additional, Verma, Pradeep, additional, Yadav, Rahul, additional, and Yadav, Rajeev Singh, additional

Published
2024
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6. Tuberculous Otitis Media: A Mysterious Ailment

Author

Saravana Selvan Velmurugan, Vivek Mariappan, Mohamed Siddique Samsudeen, Suresh Kumar Narayanan, Rhea Mathai, and Tany James Maria

Subjects
Extra Pulmonary Tuberculosis, Granulation Tissue, Antibiotics, Drug Combination, Chronic Otitis Media, Medicine, Otorhinolaryngology, RF1-547
Abstract

Abstract: Introduction: Tuberculous otitis media (TOM) is an infrequent ailment. As an uncommon form of extra-pulmonary Tuberculosis, it is often underestimated, leading to a delay in diagnosis and start of appropriate treatment. Case Series: We describe 3 cases of TOM diagnosed and treated in our institute. The typical presentation was prolonged ear discharge not responding to culture sensitive antibiotics, hard of hearing, perforation of tympanic membrane, pale whitish granulation tissue. Pure Tone Audiogram (PTA) done to evaluate the hearing loss. The granulation tissue from all the patients sent for Histopathology examination (HPE) and Cartridge Based Nucleic Acid Amplification Test (CBNAAT) examination. CBNAAT results were positive in all three patients. HPE reported as chronic inflammatory pathology. PTA revealed sensorineural hearing loss in 2 patients and conductive hearing loss in 1 patient. Treatment with regular ATT 4FDC (Anti Tubercular Treatment- Four Drug Combination) regimen was started as per weight band for 6 months. Each of them was on follow up and symptomatically improving. Discussion: TOM requires recognition in refractory chronic otitis media. Early diagnosis and intervention are essential to prevent complications and optimise outcomes. The delay in initiating therapy may lead to complications such as facial nerve palsy. This case series aims to highlight the clinical presentation, effective diagnostic modalities and treatment of tuberculous otitis media and stresses the importance of awareness among otorhinolaryngologists regarding TOM and its timely management.

Published
2024
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7. Our Experience in Endoscopic Transnasal Optic Nerve Decompression

Author

Saravana Selvan Velmurugan, VIVEK Mariappan, Mohamed Siddique Samsudeen, SURESH KUMAR Narayanan, Asith Jakkiriya Basha, and Revathi Subramanian

Subjects
OPTIC NERVE DECOMPRESSION, Medicine, Otorhinolaryngology, RF1-547
Abstract

INTRODUCTION: Traumatic optic neuropathy (TON), a severe complication following head injury, affects about 0.5% to 5% of patients with closed head injuries.1 Visual acuity (VA) loss associated with TON can be partial or complete and temporary or permanent. Increased intracanalicular pressure after an injury is considered to be one of the main pathophysiological manifestations.2 Mucoceles involving the Onodi cell and the sphenoidal sinus are rare, and optic nerve compression with decreased visual acuity may be the first presenting symptom.3. Endonasal endoscopic optic nerve decompression is a safe and highly effective treatment to reduce the hydrostatic pressure on the optic nerve in cases of optic neuropathies of various etiologies. This is to share our experience on transnasal endoscopic optic nerve decompression done for optic neuropathy due to traumatic optic neuropathy and non-traumatic optic neuropathy. CASE SERIES: A case series of three patients with traumatic optic neuropathy and one patient with non-traumatic optic neuropathy over a period of two years were studied. All four patients underwent endoscopic transnasal optic nerve decompression and surgical outcome in terms of visual recovery was observed. DISCUSSION: Endoscopic transnasal optic nerve decompression is a minimally invasive , safe and efficient method of treatment for traumatic and non-traumatic optic neuropathy .4 Our experience also suggest that surgical intervention need to be considered as early as possible especially for traumatic cases to enhance visual recovery.

Published
2024
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8. The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the luminous red galaxy sample from the anisotropic power spectrum between redshifts 0.6 and 1.0

Author

Gil-Marín, Héctor, Bautista, Julián E., Paviot, Romain, Vargas-Magaña, Mariana, de la Torre, Sylvain, Fromenteau, Sebastien, Alam, Shadab, Ávila, Santiago, Burtin, Etienne, Chuang, Chia-Hsun, Dawson, Kyle S., Hou, Jiamin, de Mattia, Arnaud, Mohammad, Faizan G., Müller, Eva-Maria, Nadathur, Seshadri, Neveux, Richard, Percival, Will J., Raichoor, Anand, Rezaie, Mehdi, Ross, Ashley J., Rossi, Graziano, Ruhlmann-Kleider, Vanina, Smith, Alex, Tamone, Amélie, Tinker, Jeremy L., Tojeiro, Rita, Wang, Yuting, Zhao, Gong-Bo, Zhao, Cheng, Brinkmann, Jonathan, Brownstein, Joel R., Choi, Peter D., Escoffier, Stephanie, de la Macorra, Axel, Moon, Jeongin, Newman, Jeffrey A., Schneider, Donald P., Seo, Hee-Jong, and Vivek, Mariappan

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We analyse the clustering of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey Data Release 16 luminous red galaxy sample (DR16 eBOSS LRG) in combination with the high redshift tail of the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey Data Release 12 (DR12 BOSS CMASS). We measure the redshift space distortions (RSD) and also extract the longitudinal and transverse baryonic acoustic oscillation (BAO) scale from the anisotropic power spectrum signal inferred from 377,458 galaxies between redshifts 0.6 and 1.0, with effective redshift of $z_{\rm eff}=0.698$ and effective comoving volume of $2.72\,{\rm Gpc}^3$. After applying reconstruction we measure the BAO scale and infer $D_H(z_{\rm eff})/r_{\rm drag} = 19.30\pm 0.56$ and $D_M(z_{\rm eff})/r_{\rm drag} =17.86 \pm 0.37$. When we perform a redshift space distortions analysis on the pre-reconstructed catalogue on the monopole, quadrupole and hexadecapole we find, $D_H(z_{\rm eff})/r_{\rm drag} = 20.18\pm 0.78$, $D_M(z_{\rm eff})/r_{\rm drag} =17.49 \pm 0.52$ and $f\sigma_8(z_{\rm eff})=0.454\pm0.046$. We combine both sets of results along with the measurements in configuration space of \cite{LRG_corr} and report the following consensus values: $D_H(z_{\rm eff})/r_{\rm drag} = 19.77\pm 0.47$, $D_M(z_{\rm eff})/r_{\rm drag} = 17.65\pm 0.30$ and $f\sigma_8(z_{\rm eff})=0.473\pm 0.044$, which are in full agreement with the standard $\Lambda$CDM and GR predictions. These results represent the most precise measurements within the redshift range $0.6\leq z \leq 1.0$ and are the culmination of more than 8 years of SDSS observations., Comment: 41 pages, 20 figures; Minor updates to match the published version in MNRAS. A summary of all SDSS BAO and RSD measurements with accompanying legacy figures can be found here: https://www.sdss.org/science/final-bao-and-rsd-measurements/ . The full cosmological interpretation of these measurements can be found here: https://www.sdss.org/science/cosmology-results-from-eboss/

Published
2020
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9. Advanced Polymer Composites for Effective Removal of Perfluorooctanoic Acid (PFOA) Pollutants From Aqueous Solutions.

Author

Rajadurai, Vijayalakshmi, Annal, Umaiyambika Neduvel, Elango, Duraisamy, Santhi, Vivek Mariappan, Devanesan, Sandhanasamy, Dixit, Saurav, Vatin, Nikolai Ivanovich, and Lo, Huang‐Mu

Abstract

Perfluorooctanoic acid (PFOA) is extensively utilized in industrial applications, posing significant environmental and health risks because of its persistence and toxicity. Effective elimination methods are vital to mitigate its adverse effects on ecosystems and human health. In this study, we investigate the potential of biomass‐derived polymer composite for PFOA adsorption in aqueous solution. Due to its unique surface interaction and porosity, the polymer‐based composite derived from sustainable biomass sources exhibits favorable adsorption characteristics. The physicochemical properties of polymer composites were characterized using FTIR, XRD, SEM‐EDS, XPS, and BET analysis. The polymer composites reached a maximum PFOA adsorption efficiency about 93.3% under optimized conditions determined by Box Behnken Design. The Langmuir isotherm model revealed and provided an adsorption capacity of PFOA about 13.98 mg g−1. Moreover, the polymer‐based composites demonstrated reusability, with removal rates of PFOA ranging from 93.3% to 52% over the course of four cycles after desorption. Our findings underscore the possibility of biomass‐derived polymer composites as long‐term and effective adsorbents for PFOA removal from aqueous environments. [ABSTRACT FROM AUTHOR]

Published
2024
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10. The incidence and grade of tubercle of zuckerkandl and its relationship to the course of recurrent laryngeal nerve in thyroid surgery

Author

Ashwin Gajendran Vedhapoodi, Vivek Mariappan, Suresh Kumar Narayanan, S Mohamed Siddique, and Venugopal Mohan Kumar

Subjects
anatomical landmark, recurrent laryngeal nerve, thyroidectomy, tubercle of zuckerkandl, Surgery, RD1-811, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

Aim of the Study: The aim is to study the incidence and grade of Zuckerkandl’s tubercle (ZT) and the course of recurrent laryngeal nerve (RLN) with respect to the grade of ZT. Settings and Design: A prospective observational anatomical study. Materials and Methods: The relationship of ZT to RLN was studied, and the size of the ZT was measured and graded according to Pelizzo’s grading system in all cases of routine thyroidectomy in 36 patients (45 sides) from December 2018 to November 2019. Results: ZT was present in 32 (71.11%) of the sides, more commonly on the right side in 24 (88.89%) with a P value of 0.001. Among the total thyroidectomy, bilateral ZT was present in 7 cases (77.78%). In the 45 sides Grade 0 was noted in 13/45 (28.89%), Grade I 14/45 (31.11%), Grade II 9/45 (20%), and Grade III 9/45 (20%) with a P value of 0.001. ZT more than 0 but less than 1 cm was the most common occurrence (Grade I and II). In the 32 sides which had ZT, 23/32 (71.88%) were Type A (posterior) and 9/32 (28.12%) were type D (lateral) with a P value of 0.01. Conclusions: The identification and meticulous dissection of ZT ensures completeness of thyroidectomy. As the size of the ZT increases, the nerve often runs posterior and medial to surface of ZT. The site of ZT can be considered an eloquent area in thyroid surgery as it lies in proximity to the RLN and superior parathyroid gland.

Published
2020
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16. Quantum chemical and experimental studies on the extraction of acid blue 80 and acid red 1 from their aquatic environment using tetrabutylammonium bromide based deep eutectic solvents

Author

Thamby, Beevi Fathima Mohamed, Santhi, Vivek Mariappan, and Ramalingam, Anantharaj

Subjects
Polymers and Plastics, Physical and Theoretical Chemistry, Surfaces, Coatings and Films
Abstract

In this study, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy, HOMO–LUMO energy gap, chemical potential (µ), electronegativity (χ), electrophilicity index (ω), global hardness (η), and global softness (s) of dyes; acid blue 80 (AB80), acid red 1 (AR1) and deep eutectic solvents: tetrabutylammonium bromide with glycerol {[TBAB][Gly]}, tetrabutylammonium bromide with decanoic acid {[TBAB][DA]} and tetrabutylammonium bromide with oleic acid {[TBAB][OA]} were predicted and calculated using quantum chemical calculation. The polarity of all the studied molecules also predicted in terms of screening charge density and plotted sigma profile and sigma potential. Further, the extraction experiment was conducted for the extraction of acid blue 80 (AB80) and acid red 1 (AR1) using tetrabutylammonium bromide with decanoic acid {[TBAB][DA]} and tetrabutylammonium bromide with oleic acid {[TBAB][OA]} as the potential solvent. The process was characterized by means of distribution coefficient and efficiency. Finally, the extraction process feasibility was studied and discussed in terms of ΔGT0, ΔHT0, and ΔST0.

Published
2023
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17. Experimental density and volumetric properties of DESs based on tetrabutylammonium bromide and used for effective extraction of naphthol green B and malachite green.

Author

Thamby, Beevi Fathima Mohamed, Santhi, Vivek Mariappan, and Ramalingam, Anantharaj

Subjects
MALACHITE green, NAPHTHOL, MOLECULAR volume, GIBBS' free energy, THERMAL expansion, HYDROPHOBIC compounds, DYES & dyeing
Abstract

BACKGROUND: To improve the quality of wastewater and thereby to meet the standards as per environmental production agency in US and UK. In the present work, Malachite green (MG) and Naphthol Green B (NGB) has been taken as model dyes in wastewater. Solvent extraction process was carried out using deep eutectic solvents (DESs) as an alternative solvent for organic and ionic liquids. RESULTS: The possible molecular interaction between DESs and selective dyes in water were analyzed and discussed in details using volumetric properties including excess molar volume VmE, partial molar volume Vi¯, excess partial molar volume V¯iE, apparent molar volume V∅i, isobaric thermal expansion (α) and excess isobaric thermal expansion (αE). Further, the extraction of selective dyes was conducted and characterized in terms of extraction efficiency (η), effect of temperature on extraction efficiency, effect of shaking time on extraction efficiency, effect of concentration on extraction efficiency, effect of HBD on extraction efficiency, distribution coefficient (D). Finally, the thermodynamic extraction feasibility was analysed by means of Gibbs free energy ΔGT0, change in enthalpy ΔHT0, and change in entropy ΔST0. CONCLUSION: There is possible molecular interaction between hydrophilic DESs and NGB/MG in water at molecular level. 96% of extraction efficiency was obtained for NGB using hydrophobic DESs like {[TBAB][DA]} and {[TBAB][OA]} whereas {[TBAB][DA]} and {[TBAB][OA]} gave above 72% removal efficiency of MG. Finally the thermodynamic feasibility of extraction process was analyzed and discussed. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Published
2023
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18. Deep eutectic solvents on extraction of bisphenol A from water matrices: COnductor like Screening MOdel for Real Solvents prediction and experimental validation

Author

Swaanika Lakshmi Narasimhan, Divya Lakshmi Parthasarathy, Anantharaj Ramalingam, Priyadarshini Seshasayee, and Vivek Mariappan Santhi

Subjects
chemistry.chemical_compound, Bisphenol A, Materials science, chemistry, Chemical engineering, Renewable Energy, Sustainability and the Environment, General Chemical Engineering, Extraction (chemistry), Experimental validation, Waste Management and Disposal, Deep eutectic solvent, Eutectic system, Conductor
Published
2021
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19. Ammonium based deep eutectic solvents (DESs) on extraction of benzothiophene from iso-octane: experiment and COSMO-RS model

Author

Chandramohan Ayyavu, Vichitra Malaiyarasan, Deepthi Jayachandran Sreekala, Anantharaj Ramalingam, and Vivek Mariappan Santhi

Subjects
Ammonium bromide, Polymers and Plastics, Extraction (chemistry), Benzothiophene, 02 engineering and technology, Decanoic acid, 021001 nanoscience & nanotechnology, Surfaces, Coatings and Films, Deep eutectic solvent, COSMO-RS, chemistry.chemical_compound, 020401 chemical engineering, chemistry, 0204 chemical engineering, Physical and Theoretical Chemistry, 0210 nano-technology, Nuclear chemistry, Octane, Eutectic system
Abstract

Densities of pure benzothiophene (BT), iso-octane (ISO), and tetra butyl ammonium bromide decanoic acid {[TBAB][DA]} as deep eutectic solvent and their binary mixtures of [BT] + [ISO], [BT] + {[TBAB][DA]} and {[TBAB][DA]} + [ISO] over the entire mole fractions were measured at different temperatures 303.15 K–353.15 K at 1 atm. From this measured density data, the solution thermodynamic properties such as excess molar volume, partial molar volume, excess partial molar volumes, apparent molar volume, isobaric expansivity, and excess isobaric expansivity were calculated. Further, this calculated excess molar volume data were correlated by Redlich-Kister polynomial fit equation. Subsequently, liquid–liquid extraction (LLE) experiment were conducted for the removal of BT from ISO using {[TBAB + DA]} at 298.15 K and 1 atm. This LLE process was characterized in terms of distribution coefficient and selectivity and thermodynamic consistency test were done by Othmer-Tobias and Hand Equations. Finally, the sigma (σ) profile and sigma (σ) potential of all the studied species were generated and analyzed using COSMO-RS model.

Published
2021
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20. Ammonium based deep eutectic solvents (DESs) on extraction of benzothiophene from iso-octane: experiment and COSMO-RS model.

Author

Santhi, Vivek Mariappan, Ramalingam, Anantharaj, Sreekala, Deepthi Jayachandran, Malaiyarasan, Vichitra, and Ayyavu, Chandramohan

Subjects
*MOLECULAR volume, *TETRAFLUOROBORATES, *EUTECTICS, *LIQUID-liquid extraction, *BINARY mixtures, *SOLVENTS, *DECANOIC acid, *CHOLINE chloride
Abstract

Densities of pure benzothiophene (BT), iso-octane (ISO), and tetra butyl ammonium bromide decanoic acid {[TBAB][DA]} as deep eutectic solvent and their binary mixtures of [BT] + [ISO], [BT] + {[TBAB][DA]} and {[TBAB][DA]} + [ISO] over the entire mole fractions were measured at different temperatures 303.15 K–353.15 K at 1 atm. From this measured density data, the solution thermodynamic properties such as excess molar volume, partial molar volume, excess partial molar volumes, apparent molar volume, isobaric expansivity, and excess isobaric expansivity were calculated. Further, this calculated excess molar volume data were correlated by Redlich-Kister polynomial fit equation. Subsequently, liquid–liquid extraction (LLE) experiment were conducted for the removal of BT from ISO using {[TBAB + DA]} at 298.15 K and 1 atm. This LLE process was characterized in terms of distribution coefficient and selectivity and thermodynamic consistency test were done by Othmer-Tobias and Hand Equations. Finally, the sigma (σ) profile and sigma (σ) potential of all the studied species were generated and analyzed using COSMO-RS model. [ABSTRACT FROM AUTHOR]

Published
2022
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24. The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the luminous red galaxy sample from the anisotropic power spectrum between redshifts 0.6 and 1.0

Author

Gil-Marín, Héctor, primary, Bautista, Julián E, additional, Paviot, Romain, additional, Vargas-Magaña, Mariana, additional, de la Torre, Sylvain, additional, Fromenteau, Sebastien, additional, Alam, Shadab, additional, Ávila, Santiago, additional, Burtin, Etienne, additional, Chuang, Chia-Hsun, additional, Dawson, Kyle S, additional, Hou, Jiamin, additional, de Mattia, Arnaud, additional, Mohammad, Faizan G, additional, Müller, Eva-Maria, additional, Nadathur, Seshadri, additional, Neveux, Richard, additional, Percival, Will J, additional, Raichoor, Anand, additional, Rezaie, Mehdi, additional, Ross, Ashley J, additional, Rossi, Graziano, additional, Ruhlmann-Kleider, Vanina, additional, Smith, Alex, additional, Tamone, Amélie, additional, Tinker, Jeremy L, additional, Tojeiro, Rita, additional, Wang, Yuting, additional, Zhao, Gong-Bo, additional, Zhao, Cheng, additional, Brinkmann, Jonathan, additional, Brownstein, Joel R, additional, Choi, Peter D, additional, Escoffier, Stephanie, additional, de la Macorra, Axel, additional, Moon, Jeongin, additional, Newman, Jeffrey A, additional, Schneider, Donald P, additional, Seo, Hee-Jong, additional, and Vivek, Mariappan, additional

Published
2020
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25. The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: BAO and RSD measurements from anisotropic clustering analysis of the quasar sample in configuration space between redshift 0.8 and 2.2

Author

Department of Energy (US), Hou, Jiamin, Sánchez, Ariel G., Ross, Ashley J., Smith, Alex, Neveux, Richard, Burtin, Etienne, Zhao, Cheng, Scoccimarro, Román, Dawson, Kyle, Mattia, Arnaud de, Macorra, Axel de la, Bourboux, H.d.M.d., Eisenstein, Daniel J., Gil-Marín, Héctor, Lyke, Brad W., Mohammad, Faizan G., Mueller, Eva-Maria, Percival, Will J., Rossi, Graziano, Vargas Magaña, Mariana, Zarrouk, Pauline, Zhao, Gong-Bo, Brinkmann, Jonathan, Brownstein, Joel R., Chuang, Chia-Hsun, Myers, Adam D., Newman, Jeffrey A., Schneider, Donald P., Vivek, Mariappan, Department of Energy (US), Hou, Jiamin, Sánchez, Ariel G., Ross, Ashley J., Smith, Alex, Neveux, Richard, Burtin, Etienne, Zhao, Cheng, Scoccimarro, Román, Dawson, Kyle, Mattia, Arnaud de, Macorra, Axel de la, Bourboux, H.d.M.d., Eisenstein, Daniel J., Gil-Marín, Héctor, Lyke, Brad W., Mohammad, Faizan G., Mueller, Eva-Maria, Percival, Will J., Rossi, Graziano, Vargas Magaña, Mariana, Zarrouk, Pauline, Zhao, Gong-Bo, Brinkmann, Jonathan, Brownstein, Joel R., Chuang, Chia-Hsun, Myers, Adam D., Newman, Jeffrey A., Schneider, Donald P., and Vivek, Mariappan

Abstract

We measure the anisotropic clustering of the quasar sample from Data Release 16 (DR16) of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey (eBOSS). A sample of 343 708 spectroscopically confirmed quasars between redshift 0.8 < z < 2.2 are used as tracers of the underlying dark matter field. In comparison with DR14 sample, the final sample doubles the number of objects as well as the survey area. In this paper, we present the analysis in configuration space by measuring the two-point correlation function and decomposing it using the Legendre polynomials. For the full-shape analysis of the Legendre multipole moments, we measure the baryon acoustic oscillation (BAO) distance and the growth rate of the cosmic structure. At an effective redshift of zeff = 1.48, we measure the comoving angular diameter distance DM(zeff)/rdrag = 30.66 ± 0.88, the Hubble distance DH(zeff)/rdrag = 13.11 ± 0.52, and the product of the linear growth rate and the rms linear mass fluctuation on scales of $8 \, h{-1}\, {\rm Mpc}$, f?8(zeff) = 0.439 ± 0.048. The accuracy of these measurements is confirmed using an extensive set of mock simulations developed for the quasar sample. The uncertainties on the distance and growth rate measurements have been reduced substantially (?45 and ?30 per cent) with respect to the DR14 results. We also perform a BAO-only analysis to cross check the robustness of the methodology of the full-shape analysis. Combining our analysis with the Fourier-space analysis, we arrive at $D{{\bf c}}-{\rm M}(z-{\rm eff})/r-{\rm drag} = 30.21 \pm 0.79$, $D{{\bf c}}-{\rm H}(z-{\rm eff})/r-{\rm drag} = 13.23 \pm 0.47$, and $f\sigma-8{{\bf c}}(z-{\rm eff}) = 0.462 \pm 0.045$.

Published
2020

26. Probing the central engine and environment of AGN using ARIES 1.3-m and 3.6-m telescopes

Author

Omar, Amitesh, Chand, Hum, Gopal-Krishna, Rakshit, Suvendu, Jalan, Priyanka, Ojha, Vineet, Srianand, Raghunathan, Vivek, Mariappan, Mishra, Sapna, Kumar, Parveen, Joshi, Ravi, and Kumar, Rathna

Subjects
spectroscopy, astrophysics, photometry, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Cosmology and Extragalactic Astrophysics, extragalactique, spectrocopie, astronomy, photométrie, astronomie, AGN, Astrophysics::Galaxy Astrophysics, astrophysique, extragalactic
Abstract

We discuss three long term observational programmes to probe the central engine and environment of active galactic nuclei (AGN) using the recently installed ARIES 1.3-m and 3.6-m telescopes. The first programme is on the photometric reverberation mapping of low luminosity AGN by mainly using the ARIES 1.3-m telescope. The major impact of this programme other than to estimate the black hole mass will be to extend the broad line region (BLR) radius-luminosity (RBLR-LAGN) relation to the unexplored low luminosity regime, and to constrain the AGN broad line region geometry. The second programme is to use long slit spectroscopy on the ARIES 3.6-m telescope to discover new high redshift quasar pairs with angular separation less than ~ 1-arcmin. Here, the background QSOs sight-line will be used to probe the environment of the foreground QSOs at kpc-Mpc scales. The major impact of this programme will be on the discovery of new pairs which have been missed in the SDSS survey due to fiber collision below 1-arcmin separation, and use them to understand about any excess overdensity around the QSO, any anisotropic emission of QSOs, and/or any episodic activity of QSOs. The third programme is related to spectral variability studies of the C IV broad absorption line (BAL) QSOs, based on low resolution spectroscopy using the ARIES 3.6-m telescope. Here, those most interesting cases will be monitored, where the BAL flow emerges afresh or disappears completely in the C IV trough of BAL QSOs sample as seen in SDSS multi-epoch observations. Continuous monitoring of such a sample will be important for our understanding of the nature and origin of the flow, along with their stability and dynamical evolution.

Published
2018
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27. The Sloan Digital Sky Survey Quasar Catalog: Fourteenth data release

Author

Anne-Marie Weijmans, Vivek Mariappan, Graziano Rossi, Jean-Paul Kneib, Kyle S. Dawson, Christophe Yèche, Julian E. Bautista, Eric Armengaud, Scott F. Anderson, Rita Tojeiro, Chelsea L. MacLeod, Nathalie Palanque-Delabrouille, Sylvain de la Torre, Michael R. Blanton, Etienne Burtin, Adam D. Myers, Hee-Jong Seo, Joel R. Brownstein, Benjamin A. Weaver, Héctor Gil-Marín, Stephanie M. LaMassa, Ian D. McGreer, W. N. Brandt, Patrick Petitjean, Ashley J. Ross, Jonathan Brinkmann, Will J. Percival, Paul J. Green, Andrea Merloni, Pauline Zarrouk, Patrick B. Hall, Éric Aubourg, Isabelle Pâris, Pasquier Noterdaeme, Jean Marc Le Goff, Brad W. Lyke, Michael Blomqvist, Donald P. Schneider, Antonis Georgakakis, Alina Streblyanska, Gong-Bo Zhao, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Lagrange de Paris, Sorbonne Universités, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), SDSS, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), ANR-16-CE31-0021,eBOSS,Sondes cosmologiques de la gravitation et de l'énergie noire(2016), The Leverhulme Trust, University of St Andrews. School of Physics and Astronomy, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Sorbonne Université (SU), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), media_common.quotation_subject, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, 01 natural sciences, Cosmology, Spectral line, Photometry (optics), surveys, quasars: general, 0103 physical sciences, QB Astronomy, Emission spectrum, Spectral resolution, 010303 astronomy & astrophysics, QC, Astrophysics::Galaxy Astrophysics, media_common, QB, Physics, 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Quasar, general [Quasars], DAS, Astrophysics - Astrophysics of Galaxies, Redshift, QC Physics, 13. Climate action, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), Catalogs, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], catalogs, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We present the Data Release 14 Quasar catalog (DR14Q) from the extended Baryon Oscillation Spectroscopic Survey (eBOSS) of the Sloan Digital Sky Survey IV (SDSS-IV). This catalog includes all SDSS-IV/eBOSS objects that were spectroscopically targeted as quasar candidates and that are confirmed as quasars via a new automated procedure combined with a partial visual inspection of spectra, have luminosities $M_{\rm i} \left[ z=2 \right] < -20.5$ (in a $\Lambda$CDM cosmology with $H_0 = 70 \ {\rm km \ s^{-1} \ Mpc ^{-1}}$, $\Omega_{\rm M} = 0.3$, and $\Omega_{\rm \Lambda} = 0.7$), and either display at least one emission line with a full width at half maximum (FWHM) larger than $500 \ {\rm km \ s^{-1}}$ or, if not, have interesting/complex absorption features. The catalog also includes previously spectroscopically-confirmed quasars from SDSS-I, II and III. The catalog contains 526,356 quasars 144,046 are new discoveries since the beginning of SDSS-IV) detected over 9,376 deg$^2$ (2,044 deg$^2$ having new spectroscopic data available) with robust identification and redshift measured by a combination of principal component eigenspectra. The catalog is estimated to have about 0.5% contamination. The catalog identifies 21,877 broad absorption line quasars and lists their characteristics. For each object, the catalog presents SDSS five-band CCD-based photometry with typical accuracy of 0.03 mag. The catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys., Comment: Accepted for publication in A&A. The catalog is available at https://data.sdss.org/sas/dr14/eboss/qso/DR14Q/DR14Q_v4_4.fits

Published
2018
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28. The clustering of the SDSS-IV extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample: measurement of the growth rate of structure from the anisotropic correlation function between redshift 0.8 and 2.2

Author

Falk Baumgarten, Patrick Petitjean, Gong-Bo Zhao, Julian E. Bautista, Will J. Percival, Sylvain de la Torre, John A. Peacock, Rossana Ruggeri, Katrin Heitmann, Ariel G. Sánchez, Rita Tojeiro, Sergio Rodríguez-Torres, Pauline Zarrouk, Yuting Wang, Etienne Burtin, Héctor Gil-Marín, Kyle S. Dawson, Adam D. Myers, Jean Marc Le Goff, Pierre Laurent, Chia-Hsun Chuang, Johan Comparat, Hee-Jong Seo, Graziano Rossi, Salman Habib, Jeremy L. Tinker, Violeta Gonzalez-Perez, Francisco Prada, Cheng Zhao, Nathalie Palanque-Delabrouille, C. Yeche, Donald P. Schneider, Joel R. Brownstein, Vivek Mariappan, Hélion du Mas des Bourboux, Isabelle Pâris, Jean-Paul Kneib, Jiamin Hou, Ashley J. Ross, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Lagrange de Paris, Sorbonne Université (SU), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay, Agence Nationale de la Recherche (France), The Ohio State University, Newton Fund, Department of Energy (US), National Science Foundation (US), National Research Foundation of Korea, Ministry of Education, Science and Technology (South Korea), Sejong University, Alfred P. Sloan Foundation, Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Sorbonne Universités, Laboratoire de Physique Nucléaire et de Hautes Énergies ( LPNHE ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Astrophysique de Marseille ( LAM ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Aix Marseille Université ( AMU ) -Centre National d'Etudes Spatiales ( CNES ), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), and University of St Andrews. School of Physics and Astronomy

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Large-scale structure of Universe, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], Cosmological parameters, Library science, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 7. Clean energy, Max planck institute, 0103 physical sciences, Dark energy, QB Astronomy, User Facility, cosmological parameters, observations [Cosmology], dark energy, 010303 astronomy & astrophysics, QC, QB, Mathematics, ) large-scale structure of Universe [(Cosmology], 010308 nuclear & particles physics, DAS, Astronomy and Astrophysics, 16. Peace & justice, QC Physics, 13. Climate action, Space and Planetary Science, cosmology: observations, Christian ministry, large-scale structure of Universe, National laboratory, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We present the clustering measurements of quasars in configuration space based on the Data Release 14 (DR14) of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey (eBOSS). This data set includes 148 659 quasars spread over the redshift range 0.8 ≤ z ≤ 2.2 and spanning 2112.9 deg2. We use the Convolution Lagrangian Perturbation Theory approach with a Gaussian Streaming model for the redshift space distortions of the correlation function and demonstrate its applicability for dark matter haloes hosting eBOSS quasar tracers. At the effective redshift zeff = 1.52, we measure the linear growth rate of structure fσ8(zeff) = 0.426 ± 0.077, the expansion rate H(zeff) = 159 -13 +12(r s fid/rs) kms-1Mpc-1, and the angular diameter distance DA(zeff) = 1850 -115 +90 (rs/r s fid) Mpc, where rs is the sound horizon at the end of the baryon drag epoch and r s fid is its value in the fiducial cosmology. The quoted uncertainties include both systematic and statistical contributions. The results on the evolution of distances are consistent with the predictions of flat Λ-cold dark matter cosmology with Planck parameters, and the measurement of fσ8 extends the validity of General Relativity to higher redshifts (z > 1). This paper is released with companion papers using the same sample. The results on the cosmological parameters of the studies are found to be in very good agreement, providing clear evidence of the complementarity and of the robustness of the first full-shape clustering measurements with the eBOSS DR14 quasar sample. © 2017 The Authors., PZ and EB acknowledge support from the P2IO LabEx (reference ANR-10-LABX-0038). HGM acknowledges support from the Labex ILP (reference ANR-10-LABX-63) part of the Idex SUPER, and received financial state aid managed by the Agence Nationalede la Recherche, as part of the programme Investissements d'avenir under the reference ANR-11-IDEX-0004-02. AJR is grateful for support from the Ohio State University Center for Cosmology and ParticlePhysics. GBZ is supported by NSFC Grants 1171001024 and 11673025. GBZ is also supported by a Royal Society Newton Advanced Fellowship, hosted by University of Portsmouth. SH's and KH's work was supported under the U.S. Department of Energy contract DE-AC02-06CH11357. GBZ is supported by NSFC Grant No. 11673025, and by a Royal Society Newton Advanced Fellowship. GR acknowledges support from the National Research Foundation of Korea (NRF) through Grant No. 2017077508 funded by the Korean Ministry of Education, Science and Technology (MoEST), and from the faculty research fund of Sejong University in 2018. Funding for SDSS-III and SDSS-IV has been provided by the Alfred P. Sloan Foundation and Participating Institutions. Additional funding for SDSS-III comes from the National Science Foundation and the U.S. Department of Energy Office of Science. Further information about both projects is available at www.sdss.org. SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions in both collaborations. In SDSS-III, these include the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. The Participating Institutions in SDSS-IV are CarnegieMellon University, Colorado University, Boulder, Harvard-Smithsonian Center for Astrophysics Participation Group, Johns Hopkins University, Kavli Institute for the Physics and Mathematics of the Universe Max-Planck-Institut fuer Astrophysik (MPA Garching), Max-Planck-Institut fuer Extraterrestrische Physik (MPE), Max-Planck-Institut fuer Astronomie (MPIA Heidelberg), National Astronomical Observatories of China, New Mexico State University, New York University, The Ohio State University, Penn State University, Shanghai Astronomical Observatory, United Kingdom Participation Group, University of Portsmouth, University of Utah, University of Wisconsin, and Yale University. This research used resources of the Argonne Leadership Computing Facility, which is a DOE Office of Science User Facility supported under contract DE-AC02-06CH11357. This work made use of the facilities and staff of the UK Sciama High Performance Computing cluster supported by the ICG, SEPNet, and the University of Portsmouth. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No.r DE-AC02-05CH11231.

Published
2018
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29. The Time-Domain Spectroscopic Survey: Target Selection for Repeat Spectroscopy

Author

John J. Ruan, W. N. Brandt, Nurten Filiz Ak, Kyle S. Dawson, Suzanne L. Hawley, Michael R. Blanton, Jessie C. Runnoe, Sarah J. Schmidt, Amy Lebleu, Chelsea L. MacLeod, Eugene A. Magnier, Jeremy L. Tinker, Daniel Hoover, Michael Eracleous, Jenny E. Greene, Keivan G. Stassun, Rachael Amaro, C. Z. Waters, Eric Morganson, K. C. Chambers, R. P. Kudritzki, José G. Fernández-Trincado, Matthew A. Bershady, Sean McGraw, Nigel Metcalfe, Carles Badenes, Adam D. Myers, Hee-Jong Seo, Axel Schwope, Scott F. Anderson, Vivek Mariappan, Yue Shen, Catherine J. Grier, Isabelle Pâris, Patrick B. Hall, Donald P. Schneider, Paul J. Green, Nick Kaiser, Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules ( UTINAM ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Université de Franche-Comté (UFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, RR Lyrae variable, 01 natural sciences, surveys, quasars: general, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Physics, Supermassive black hole, 010308 nuclear & particles physics, White dwarf, Astronomy and Astrophysics, Quasar, Astrophysics - Astrophysics of Galaxies, Carbon star, stars: variables: general, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, Variable star, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

As astronomers increasingly exploit the information available in the time domain, spectroscopic variability in particular opens broad new channels of investigation. Here we describe the selection algorithms for all targets intended for repeat spectroscopy in the Time Domain Spectroscopic Survey (TDSS), part of the extended Baryon Oscillation Spectroscopic Survey within the Sloan Digital Sky Survey-IV. Also discussed are the scientific rationale and technical constraints leading to these target selections. The TDSS includes a large "Repeat Quasar Spectroscopy" (RQS) program delivering ~13,000 repeat spectra of confirmed SDSS quasars, and several smaller "Few-Epoch Spectroscopy" (FES) programs targeting specific classes of quasars as well as stars. The RQS program aims to provide a large and diverse quasar data set for studying variations in quasar spectra on timescales of years, a comparison sample for the FES quasar programs, and opportunity for discovering rare, serendipitous events. The FES programs cover a wide variety of phenomena in both quasars and stars. Quasar FES programs target broad absorption line quasars, high signal-to-noise ratio normal broad line quasars, quasars with double-peaked or very asymmetric broad emission line profiles, binary supermassive black hole candidates, and the most photometrically variable quasars. Strongly variable stars are also targeted for repeat spectroscopy, encompassing many types of eclipsing binary systems, and classical pulsators like RR Lyrae. Other stellar FES programs allow spectroscopic variability studies of active ultracool dwarf stars, dwarf carbon stars, and white dwarf/M dwarf spectroscopic binaries. We present example TDSS spectra and describe anticipated sample sizes and results., 26 pages, 11 figures, replaced with accepted version to AJ

Published
2017
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30. The SDSS-IV extended Baryon Oscillation Spectroscopic Survey : Luminous Red Galaxy Target Selection

Author

Jeremy L. Tinker, Vivek Mariappan, Abhishek Prakash, Francisco Prada, Guangtun Zhu, Rita Tojeiro, A. C. Rosell, Stephen Bailey, Sandhya M. Rao, Cameron K. McBride, Kyle S. Dawson, Joel R. Brownstein, Jean-Paul Kneib, David J. Schlegel, Donald P. Schneider, Julian E. Bautista, Jeffrey A. Newman, Adam S. Bolton, Ashley J. Ross, Timothée Delubac, Shirley Ho, Dustin Lang, Johan Comparat, Michael R. Blanton, Hee-Jong Seo, Adam D. Myers, Timothy C. Licquia, Beth Reid, Will J. Percival, University of St Andrews. School of Physics and Astronomy, UAM. Departamento de Física Teórica, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Departamento de FisicaTeorica e IFT-UAM/CSIC, Universidad Autónoma de Madrid (UAM), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), McMaster University [Hamilton, Ontario], EPFL Laboratoire d’astrophysique, Ecole Polytechnique Fédérale de Lausanne (EPFL), Department of Physics and Astronomy [Pittsburgh], University of Pittsburgh (PITT), Pennsylvania Commonwealth System of Higher Education (PCSHE)-Pennsylvania Commonwealth System of Higher Education (PCSHE), Universidad Autonoma de Madrid (UAM), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES)

Subjects
Infrared, Astrophysics, 01 natural sciences, Atomic, Physical Chemistry, Spectral line, Particle and Plasma Physics, QB Astronomy, 010303 astronomy & astrophysics, media_common, QB, Physics, Oscillation, Cosmology: observations, Astrophysics::Instrumentation and Methods for Astrophysics, 3rd-DAS, observations [cosmology], astro-ph.CO, photometry [galaxies], Astronomical and Space Sciences, Physical Chemistry (incl. Structural), Astrophysics - Cosmology and Nongalactic Astrophysics, Galaxies: general, Cosmology and Gravitation, Cosmology and Nongalactic Astrophysics (astro-ph.CO), media_common.quotation_subject, astro-ph.GA, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astronomy & Astrophysics, Galaxies: distances and redshifts, Methods: data analysis, 0103 physical sciences, data analysis [methods], Nuclear, Astrophysics::Galaxy Astrophysics, 010308 nuclear & particles physics, Homogeneity (statistics), Molecular, Física, Astronomy and Astrophysics, Galaxies: photometry, Astrophysics - Astrophysics of Galaxies, Galaxy, Redshift, Baryon, 13. Climate action, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), distances and redshifts [galaxies], Catalogs, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], uploaded-in-3-months-elsewhere, catalogs, general [galaxies]
Abstract

We describe the algorithm used to select the Luminous Red Galaxy (LRG) sample for the extended Baryon Oscillation Spectroscopic Survey (eBOSS) of the Sloan Digital Sky Survey IV (SDSS-IV) using photometric data from both the SDSS and the Wide-Field Infrared Survey Explorer (WISE). LRG targets are required to meet a set of color selection criteria and have z-band and i-band MODEL magnitudes z < 19.95 and 19.9 < i < 21.8, respectively. Our algorithm selects roughly 50 LRG targets per square degree, the great majority of which lie in the redshift range 0.6 < z < 1.0 (median redshift 0.71). We demonstrate that our methods are highly effective at eliminating stellar contamination and lower-redshift galaxies. We perform a number of tests using spectroscopic data from SDSS-III/BOSS to determine the redshift reliability of our target selection and its ability to meet the science requirements of eBOSS. The SDSS spectra are of high enough signal-to-noise ratio that at least 89% of the target sample yields secure redshift measurements. We also present tests of the uniformity and homogeneity of the sample, demonstrating that it should be clean enough for studies of the large-scale structure of the universe at higher redshifts than SDSS-III/BOSS LRGs reached., Submitted in ApJS, 15 pages, 10 figures

Published
2016
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31. The SDSS-IV Extended Baryon Oscillation Spectroscopic Survey : overview and early data

Author

Joe Huehnerhoff, Jo Bovy, Jean-Marc Le Goff, Nicolás G. Busca, Matthew A. Bershady, Will J. Percival, Yipeng Jing, Marcio A. G. Maia, Conor Sayres, Diana Holder, Xiaohui Fan, Eric Jullo, Flavia Sobreira, Sergio Rodríguez-Torres, Vikrant Kamble, Antonio D. Montero-Dorta, Yu Liang, Andreas A. Berlind, Patrick Gaulme, Beth Reid, Stephen Bailey, Peter Nugent, Andrea Merloni, Peter M. Frinchaboy, Dmitry Bizyaev, A. C. Rosell, Gong-Bo Zhao, Tracy Naugle, Yen-Ting Lin, Vivek Mariappan, Zhongxu Zhai, Julien Guy, Hélion du Mas des Bourboux, Shirley Ho, Martin White, Éric Aubourg, Abhishek Prakash, Pasquier Noterdaeme, Yuting Wang, Audrey Oravetz, Dustin Lang, Uroš Seljak, W. N. Brandt, Demitri Muna, Patrick Petitjean, Sylvain de la Torre, M. C. Cousinou, Ian D. McGreer, Pierre Laurent, Adam D. Myers, Isabelle Paris, Andres Meza, John J. Ruan, Franco D. Albareti, Etienne Burtin, Kyle S. Dawson, Adam S. Bolton, Alina Streblyanska, Nikhil Padmanabhan, Marcos Lima, Chia-Hsun Chuang, Kaike Pan, Benjamin A. Weaver, Daniel J. Eisenstein, Branimir Sesar, Mariana Vargas-Magaña, Ashley J. Ross, Alice Pisani, Axel de la Macorra, Mark A. Klaene, Nathalie Palanque-Delabrouille, Karen Kinemuchi, Nicholas R. MacDonald, Rita Tojeiro, Nicolas Clerc, Nao Suzuki, Scott F. Anderson, Dan Long, John A. Peacock, Kirpal Nandra, Johan Comparat, D. Kirkby, Anze Slosar, Timothy A. Hutchinson, Michael Blomqvist, Donald P. Schneider, Stephanie Escoffier, Jeremy L. Tinker, Charling Tao, Irene Cruz-González, Jon Brinkmann, Michael Eracleous, Francisco-Shu Kitaura, Hu Zou, Elena Malanushenko, Yiping Shu, Anand Raichoor, W. M. Wood-Vasey, Andreu Font-Ribera, Tom Dwelly, J. Ridl, Graziano Rossi, Hee-Jong Seo, Britt Lundgren, Sarah Shandera, Brice Ménard, Luiz N. da Costa, Shadab Alam, Ricardo L. C. Ogando, Christophe Yèche, Daniel Oravetz, Matthew M. Pieri, Jean-Paul Kneib, Julian E. Bautista, Weipeng Lin, Mara Salvato, Antonis Georgakakis, Alexis Finoguenov, Hong Guo, Florian Beutler, Guangtun Zhu, Jeremy Darling, Zheng Zheng, Frances Cope, Donna Taylor, Francisco Prada, David H. Weinberg, Cheng Li, Rupert A. C. Croft, Joel R. Brownstein, Viktor Malanushenko, Paul J. Green, Jeffrey A. Newman, John K. Parejko, David J. Schlegel, Matthew D. Olmstead, Russ R. Laher, Cameron K. McBride, Cheng Zhao, Timothée Delubac, James Rich, Michael R. Blanton, Eric Armengaud, Anne Ealet, Zheng Cai, Qiufan Lin, University of St Andrews. School of Physics and Astronomy, AVL, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy and Astrophysics [PennState], Pennsylvania State University (Penn State), Penn State System-Penn State System, Departamento de FisicaTeorica e IFT-UAM/CSIC, Universidad Autónoma de Madrid (UAM), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), EPFL Laboratoire d’astrophysique, Ecole Polytechnique Fédérale de Lausanne (EPFL), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Research Institute of Forest Resource Information Techniques, Chinese Academy of Forestry, Centre Hospitalier Universitaire de Dijon - Hôpital François Mitterrand (CHU Dijon), McMaster University [Hamilton, Ontario], Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Irvine], University of California [Irvine] (UC Irvine), University of California (UC)-University of California (UC), Département de Physique des Particules (ex SPP) (DPhP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Shanghai Astronomical Observatory [Shanghai] (SHAO), Chinese Academy of Sciences [Beijing] (CAS), Departamento de Fisica Matematica, Universidade de São Paulo = University of São Paulo (USP), Max-Planck-Institut für Astrophysik (MPA), Department of Physics and Astronomy [Pittsburgh], University of Pittsburgh (PITT), Pennsylvania Commonwealth System of Higher Education (PCSHE)-Pennsylvania Commonwealth System of Higher Education (PCSHE), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Universidad de Chile = University of Chile [Santiago] (UCHILE), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Lawrence Berkeley National Laboratory [Berkeley] (LBNL), APC - Cosmologie, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Department of Electrical and Computer Engineering [Minneapolis] (ECE), University of Minnesota [Twin Cities] (UMN), University of Minnesota System-University of Minnesota System, China National Research Center of Intelligent Equipment for Agriculture [Beijing] (NRCIEA), Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Shandong University, Laboratoire de Chimie - UMR5182 (LC), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Universidad Autonoma de Madrid (UAM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), Laboratoire d'Astrophysique, Ecole Polytechnique Fédérale de Lausanne (EPFL), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), University of California [Irvine] (UCI), University of California-University of California, Département de Physique des Particules (ex SPP) (DPP), Universidade de São Paulo (USP), Universidad Santiago de Chile, PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-AstroParticule et Cosmologie (APC (UMR_7164)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, University of Minnesota [Twin Cities], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), UAM. Departamento de Física Teórica, Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Cosmology and Gravitation, Cosmology and Nongalactic Astrophysics (astro-ph.CO), FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, 01 natural sciences, surveys, Tests of general relativity, 0103 physical sciences, ST/K0090X/1, QB Astronomy, Emission spectrum, observations [Cosmology], 010303 astronomy & astrophysics, STFC, Astrophysics::Galaxy Astrophysics, QC, QB, Physics, 010308 nuclear & particles physics, Física, RCUK, Astronomy and Astrophysics, Quasar, 3rd-DAS, Redshift, Galaxy, Baryon, QC Physics, Space and Planetary Science, cosmology: observations, astro-ph.CO, Baryon acoustic oscillations, Neutrino, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The Astrophysical Journal 151.2 (2016): 44 reproduced by permission of the AAS, In a six-year program started in 2014 July, the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) will conduct novel cosmological observations using the BOSS spectrograph at Apache Point Observatory. These observations will be conducted simultaneously with the Time Domain Spectroscopic Survey (TDSS) designed for variability studies and the Spectroscopic Identification of eROSITA Sources (SPIDERS) program designed for studies of X-ray sources. In particular, eBOSS will measure with percent-level precision the distance-redshift relation with baryon acoustic oscillations (BAO) in the clustering of matter. eBOSS will use four different tracers of the underlying matter density field to vastly expand the volume covered by BOSS and map the large-scale-structures over the relatively unconstrained redshift range 0.6 < z < 2.2. Using more than 250,000 new, spectroscopically confirmed luminous red galaxies at a median redshift z = 0.72, we project that eBOSS will yield measurements of the angular diameter distance dA(z) to an accuracy of 1.2% and measurements of H(z) to 2.1% when combined with the z > 0.6 sample of BOSS galaxies. With ∼195,000 new emission line galaxy redshifts, we expect BAO measurements of dA(z) to an accuracy of 3.1% and H(z) to 4.7% at an effective redshift of z = 0.87. A sample of more than 500,000 spectroscopically confirmed quasars will provide the first BAO distance measurements over the redshift range 0.9 < z < 2.2, with expected precision of 2.8% and 4.2% on dA(z) and H(z), respectively. Finally, with 60,000 new quasars and re-observation of 60,000 BOSS quasars, we will obtain new Lyα forest measurements at redshifts z > 2.1; these new data will enhance the precision of dA(z) and H(z) at z > 2.1 by a factor of 1.44 relative to BOSS. Furthermore, eBOSS will provide improved tests of General Relativity on cosmological scales through redshift-space distortion measurements, improved tests for non-Gaussianity in the primordial density field, and new constraints on the summed mass of all neutrino species. Here, we provide an overview of the cosmological goals, spectroscopic target sample, demonstration of spectral quality from early data, and projected cosmological constraints from eBOSS, K.D. acknowledges support from the U.S. Department of Energy under Grant DE-SC000995. J.P.K. and T.D. acknowledge support from the ERC advanced grant LIDA. W.J.P. acknowledges support from the UK STFC through the consolidated grant ST/K0090X/1, and from the European Research Council through grant Darksurvey

Published
2016
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32. Our Experience with Maxillectomies: A Retrospective Decade Study

Author

M. K. Rajasekar, Narendrakumar Veerasigamani, and Vivek Mariappan

Subjects
Otorhinolaryngology, business.industry, Medicine, business
Abstract

Objective The aim of the study is to evaluate the age, sex, site of lesion, histopathological diagnosis, and recurrence rate of the maxillectomy patients. Materials and methods A retrospective study was done in 42 patients, who underwent maxillectomy for malignant growth of the nose and paranasal sinuses from 2006 to 2015 at our center. Results The most common age group is 55 to 65 years (73.8), with male predominance (66.7%). Among symptoms prevalent is nasal obstruction (47%). Maxillary sinus is the most common site of origin (61.9%). Squamous cell carcinoma is the most common histopathological diagnosis (52.4%) and recurrence rate is 16%. Conclusion Exact clearance, reconstruction, postoperative care, and perfect teamwork play a vital role. Thus, successful outcome of maxillectomy is multifactorial. How to cite this article Rajasekar MK, Mariappan V, Veerasigamani N. Our Experience with Maxillectomies: A Retrospective Decade Study. Clin Rhinol An Int J 2017;10(2):58-61.

Published
2009
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33. The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: final emission line galaxy target selection

Author

Gong-Bo Zhao, J. A. Newmann, Jean-Paul Kneib, N. Palanque-Delabrouille, Arjun Dey, Timothée Delubac, Eric Jullo, Kyle S. Dawson, Dustin Lang, Ch. Yèche, Guangtun Zhu, John Moustakas, Julian E. Bautista, Will J. Percival, Jeremy L. Tinker, Anand Raichoor, Francisco Prada, Y. Wang, Hee-Jong Seo, Johan Comparat, David J. Schlegel, Ashley J. Ross, Vivek Mariappan, Claudio Gorgoni, Joel R. Brownstein, Département de Physique des Particules (ex SPP) (DPhP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), EPFL Laboratoire d’astrophysique, Ecole Polytechnique Fédérale de Lausanne (EPFL), Département de Physique des Particules (ex SPP) (DPP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Laboratoire d'Astrophysique de Marseille ( LAM ), and Aix Marseille Université ( AMU ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National d'Etudes Spatiales ( CNES ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), Stellar population, media_common.quotation_subject, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], astro-ph.GA, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 0103 physical sciences, Emission spectrum, 010303 astronomy & astrophysics, STFC, Astrophysics::Galaxy Astrophysics, media_common, Physics, ST/N00180X/1, 010308 nuclear & particles physics, Oscillation, Astronomy, RCUK, Astronomy and Astrophysics, Redshift survey, Astrophysics - Astrophysics of Galaxies, methods: data analysis, Galaxy, Redshift, Baryon, galaxies: photometry, Space and Planetary Science, Sky, Astrophysics of Galaxies (astro-ph.GA), cosmology: observations, astro-ph.CO, galaxies: stellar content, ST/N000668/1, large-scale structure of Universe, galaxies: distances and redshifts, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We describe the algorithm used to select the Emission Line Galaxy (ELG) sample at $z \sim 0.85$ for the extended Baryon Oscillation Spectroscopic Survey of the Sloan Digital Sky Survey IV, using photometric data from the DECam Legacy Survey. Our selection is based on a selection box in the $g-r$ vs. $r-z$ colour-colour space and a cut on the $g$-band magnitude, to favour galaxies in the desired redshift range with strong [OII] emission. It provides a target density of 200 deg$^{-2}$ on the North Galactic Cap (NGC) and of 240 deg$^{-2}$ on the South Galactic Cap (SGC), where we use a larger selection box because of deeper imaging. We demonstrate that this selection passes the eBOSS requirements in terms of homogeneity. About 50,000 ELGs have been observed since the observations have started in 2016, September. These roughly match the expected redshift distribution, though the measured efficiency is slightly lower than expected. The efficiency can be increased by enlarging the redshift range and with incoming pipeline improvement. The cosmological forecast based on these first data predict $\sigma_{D_V}/D_V = 0.023$, in agreement with previous forecasts. Lastly, we present the stellar population properties of the ELG SGC sample. Once observations are completed, this sample will be suited to provide a cosmological analysis at $z \sim 0.85$, and will pave the way for the next decade of massive spectroscopic cosmological surveys, which heavily rely on ELGs. The target catalogue over the SGC will be released along with DR14., Comment: Submitted to MNRAS, 18 pages

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34. Advanced Polymer Composites for Effective Removal of Perfluorooctanoic Acid (PFOA) Pollutants From Aqueous Solutions.

Author

Rajadurai V, Annal UN, Elango D, Santhi VM, Devanesan S, Dixit S, Vatin NI, and Lo HM

Subjects
Adsorption, Water Purification methods, Biomass, Surface Properties, Solutions, Fluorocarbons chemistry, Fluorocarbons isolation & purification, Caprylates chemistry, Caprylates isolation & purification, Water Pollutants, Chemical isolation & purification, Water Pollutants, Chemical chemistry, Polymers chemistry
Abstract

Perfluorooctanoic acid (PFOA) is extensively utilized in industrial applications, posing significant environmental and health risks because of its persistence and toxicity. Effective elimination methods are vital to mitigate its adverse effects on ecosystems and human health. In this study, we investigate the potential of biomass-derived polymer composite for PFOA adsorption in aqueous solution. Due to its unique surface interaction and porosity, the polymer-based composite derived from sustainable biomass sources exhibits favorable adsorption characteristics. The physicochemical properties of polymer composites were characterized using FTIR, XRD, SEM-EDS, XPS, and BET analysis. The polymer composites reached a maximum PFOA adsorption efficiency about 93.3% under optimized conditions determined by Box Behnken Design. The Langmuir isotherm model revealed and provided an adsorption capacity of PFOA about 13.98 mg g -1 . Moreover, the polymer-based composites demonstrated reusability, with removal rates of PFOA ranging from 93.3% to 52% over the course of four cycles after desorption. Our findings underscore the possibility of biomass-derived polymer composites as long-term and effective adsorbents for PFOA removal from aqueous environments., (© 2024 John Wiley & Sons Ltd.)

Published
2024
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