{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T20:06:33Z","timestamp":1784664393722,"version":"3.55.0"},"reference-count":74,"publisher":"SAGE Publications","issue":"12","license":[{"start":{"date-parts":[[2012,12,1]],"date-time":"2012-12-01T00:00:00Z","timestamp":1354320000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Astrobiology"],"published-print":{"date-parts":[[2012,12]]},"abstract":"<jats:p>\n                    Understanding whether M dwarf stars may host habitable planets with Earth-like atmospheres and biospheres is a major goal in exoplanet research. If such planets exist, the question remains as to whether they could be identified via spectral signatures of biomarkers. Such planets may be exposed to extreme intensities of cosmic rays that could perturb their atmospheric photochemistry. Here, we consider stellar activity of M dwarfs ranging from quiet up to strong flaring conditions and investigate one particular effect upon biomarkers, namely, the ability of secondary electrons caused by stellar cosmic rays to break up atmospheric molecular nitrogen (N\n                    <jats:sub>2<\/jats:sub>\n                    ), which leads to production of nitrogen oxides (NO\n                    <jats:sub>\n                      <jats:italic toggle=\"yes\">x<\/jats:italic>\n                    <\/jats:sub>\n                    ) in the planetary atmosphere, hence affecting biomarkers such as ozone (O\n                    <jats:sub>3<\/jats:sub>\n                    ). We apply a stationary model, that is, without a time dependence; hence we are calculating the limiting case where the atmospheric chemistry response time of the biomarkers is assumed to be slow and remains constant compared with rapid forcing by the impinging stellar flares. This point should be further explored in future work with time-dependent models. We estimate the NO\n                    <jats:sub>\n                      <jats:italic toggle=\"yes\">x<\/jats:italic>\n                    <\/jats:sub>\n                    production using an air shower approach and evaluate the implications using a climate-chemical model of the planetary atmosphere. O\n                    <jats:sub>3<\/jats:sub>\n                    formation proceeds via the reaction O+O\n                    <jats:sub>2<\/jats:sub>\n                    +M\u2192O\n                    <jats:sub>3<\/jats:sub>\n                    +M. At high NO\n                    <jats:sub>\n                      <jats:italic toggle=\"yes\">x<\/jats:italic>\n                    <\/jats:sub>\n                    abundances, the O atoms arise mainly from NO\n                    <jats:sub>2<\/jats:sub>\n                    photolysis, whereas on Earth this occurs via the photolysis of molecular oxygen (O\n                    <jats:sub>2<\/jats:sub>\n                    ). For the flaring case, O\n                    <jats:sub>3<\/jats:sub>\n                    is mainly destroyed via direct titration, NO+O\n                    <jats:sub>3<\/jats:sub>\n                    \u2192NO\n                    <jats:sub>2<\/jats:sub>\n                    +O\n                    <jats:sub>2<\/jats:sub>\n                    , and not via the familiar catalytic cycle photochemistry, which occurs on Earth. For scenarios with low O\n                    <jats:sub>3<\/jats:sub>\n                    , Rayleigh scattering by the main atmospheric gases (O\n                    <jats:sub>2<\/jats:sub>\n                    , N\n                    <jats:sub>2<\/jats:sub>\n                    , and CO\n                    <jats:sub>2<\/jats:sub>\n                    ) became more important for shielding the planetary surface from UV radiation. A major result of this work is that the biomarker O\n                    <jats:sub>3<\/jats:sub>\n                    survived all the stellar-activity scenarios considered except for the strong case, whereas the biomarker nitrous oxide (N\n                    <jats:sub>2<\/jats:sub>\n                    O) could survive in the planetary atmosphere under all conditions of stellar activity considered here, which clearly has important implications for missions that aim to detect spectroscopic biomarkers. Key Words: M dwarf\u2014Atmosphere\u2014Earth-like\u2014Biomarkers\u2014Stellar cosmic rays. Astrobiology 12, 1109\u20131122.\n                  <\/jats:p>","DOI":"10.1089\/ast.2011.0682","type":"journal-article","created":{"date-parts":[[2012,12,10]],"date-time":"2012-12-10T09:45:37Z","timestamp":1355132737000},"page":"1109-1122","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":64,"title":["Response of Atmospheric Biomarkers to NO\n                    <sub>\n                      <i>x<\/i>\n                    <\/sub>\n                    -Induced Photochemistry Generated by Stellar Cosmic Rays for Earth-like Planets in the Habitable Zone of M Dwarf Stars"],"prefix":"10.1177","volume":"12","author":[{"given":"John Lee","family":"Grenfell","sequence":"first","affiliation":[{"name":"Technische Universit\u00e4t Berlin (TUB)","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean-Mathias","family":"Grie\u00dfmeier","sequence":"additional","affiliation":[{"name":"ASTRON","place":["the Netherlands"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip","family":"von Paris","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Planetenforschung","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A. Beate C.","family":"Patzer","sequence":"additional","affiliation":[{"name":"Technische Universit\u00e4t Berlin (TUB)","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helmut","family":"Lammer","sequence":"additional","affiliation":[{"name":"\u00d6sterreichische Akademie der Wissenschaften","place":["Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara","family":"Stracke","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Planetenforschung","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefanie","family":"Gebauer","sequence":"additional","affiliation":[{"name":"Technische Universit\u00e4t Berlin (TUB)","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Franz","family":"Schreier","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Methodik der Fernerkundung","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heike","family":"Rauer","sequence":"additional","affiliation":[{"name":"Technische Universit\u00e4t Berlin (TUB)","place":["Germany"]},{"name":"Institut f\u00fcr Planetenforschung","place":["Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2012,12,1]]},"reference":[{"key":"e_1_3_3_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.physletb.2008.07.018"},{"key":"e_1_3_3_3_1","doi-asserted-by":"publisher","DOI":"10.1086\/309426"},{"key":"e_1_3_3_4_1","first-page":"853","article-title":"Passage of particles through matter","volume":"592","author":"Bichsel H.","year":"2005","unstructured":"Bichsel H., , Groom D.E., , Klein S.R. 2005. Passage of particles through matter. Phys Lett B, 592:853\u2013998.","journal-title":"Phys Lett B"},{"key":"e_1_3_3_5_1","volume-title":"Atmospheric Chemistry and Global Change","author":"Brasseur G.P.","year":"1999","unstructured":"Brasseur G.P., , Orlando J.J., , Tyndall G.S. 1999. Atmospheric Chemistry and Global Change. Oxford University Press: New York."},{"key":"e_1_3_3_6_1","first-page":"103","article-title":"A theory of upper atmosphere ozone","volume":"3","author":"Chapman S.","year":"1930","unstructured":"Chapman S. 1930. A theory of upper atmosphere ozone. Memoirs of the Royal Meteorological Society, 3:103\u2013125.","journal-title":"Memoirs of the Royal Meteorological Society"},{"key":"e_1_3_3_7_1","volume-title":"U.S. Standard Atmosphere, 1976, published jointly by the National Oceanic and Atmospheric Administration","author":"COESA (U.S. Committee on Extension to the Standard Atmosphere)","year":"1976","unstructured":"COESA (U.S. Committee on Extension to the Standard Atmosphere). 1976. U.S. Standard Atmosphere, 1976, published jointly by the National Oceanic and Atmospheric Administration. the National Aeronautics and Space Administration, and the U.S. Air Force: Washington DC."},{"key":"e_1_3_3_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/qj.49709640815"},{"key":"e_1_3_3_9_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2010.0528"},{"key":"e_1_3_3_10_1","doi-asserted-by":"publisher","DOI":"10.1029\/2005GL023975"},{"key":"e_1_3_3_11_1","doi-asserted-by":"publisher","DOI":"10.1086\/509106"},{"key":"e_1_3_3_12_1","first-page":"35","volume-title":"Interplanetary Particle Environment. Proceedings of a Conference","author":"Feynman J.G.","year":"1988","unstructured":"Feynman J.G., , Gabriel S. 1988. The effects of high energy particles on planetary missions. Interplanetary Particle Environment. Proceedings of a Conference Feynman J., , Gabriel S. JPL publication 88-28, Jet Propulsion Laboratory Pasadena, CA, 35\u201347."},{"key":"e_1_3_3_13_1","doi-asserted-by":"publisher","DOI":"10.1029\/92JA02670"},{"key":"e_1_3_3_14_1","doi-asserted-by":"publisher","DOI":"10.1086\/176150"},{"key":"e_1_3_3_15_1","first-page":"353","volume-title":"15th International Cosmic Ray Conference","volume":"8","author":"Gaisser T.K.","year":"1977","unstructured":"Gaisser T.K., , Hillas A.M. 1977. Reliability of the method of constant intensity cuts for reconstructing the average development of vertical showers. 15th International Cosmic Ray Conference, Plovdiv, Bulgaria, August 13\u201326, 1977Conference Papers8. B'lgarska Akademiia na Naukite, Sofia, 353\u2013357."},{"key":"e_1_3_3_16_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.solener.2003.08.039"},{"key":"e_1_3_3_17_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11214-008-9482-5"},{"key":"e_1_3_3_18_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF02702527"},{"key":"e_1_3_3_19_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2006.0129"},{"key":"e_1_3_3_20_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.pss.2006.09.002"},{"key":"e_1_3_3_21_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.icarus.2010.09.015"},{"key":"e_1_3_3_22_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2005.5.587"},{"key":"e_1_3_3_23_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.icarus.2008.09.015"},{"key":"e_1_3_3_24_1","first-page":"385","volume-title":"Solar and Stellar Variability: Impact on Earth and Planets, Proceedings of the IAU Symposium No. 264","author":"Grie\u00dfmeier J.-M.","year":"2010","unstructured":"Grie\u00dfmeier J.-M., , Khodachenko M., , Lammer H., , Grenfell J.L., , Stadelmann A., , Motschmann U. 2010. Stellar activity and magnetic shielding. Solar and Stellar Variability: Impact on Earth and Planets, Proceedings of the IAU Symposium No. 264 Kosovichev A.G., , Andrei A.H., , Rozelot J.-P. International Astronomical Union Paris, 385\u2013394."},{"key":"e_1_3_3_25_1","doi-asserted-by":"publisher","DOI":"10.1086\/344614"},{"key":"e_1_3_3_26_1","doi-asserted-by":"publisher","DOI":"10.1021\/ie50510a045"},{"key":"e_1_3_3_27_1","doi-asserted-by":"publisher","DOI":"10.1029\/JA082i016p02157"},{"key":"e_1_3_3_28_1","first-page":"237","volume-title":"Proceedings of the 21st International Cosmic Ray Conference","volume":"5","author":"Hamilton D.C.","year":"1990","unstructured":"Hamilton D.C., , Mason G.M., , McDonald F.B. 1990. The radial dependence of the peak flux and fluence in solar energetic particle events. Proceedings of the 21st International Cosmic Ray Conference. 5:237\u2013240."},{"key":"e_1_3_3_29_1","doi-asserted-by":"publisher","DOI":"10.1086\/307954"},{"key":"e_1_3_3_30_1","first-page":"249","article-title":"Dynamics of flares on late-type dMe stars","volume":"238","author":"Houdebine E.R.","year":"1990","unstructured":"Houdebine E.R., , Foing B., , Rodono M. 1990. Dynamics of flares on late-type dMe stars. Astron Astrophys, 238:249\u2013255.","journal-title":"Astron Astrophys"},{"key":"e_1_3_3_31_1","doi-asserted-by":"publisher","DOI":"10.1029\/JC085iC12p07495"},{"key":"e_1_3_3_32_1","doi-asserted-by":"publisher","DOI":"10.1029\/2000JD900010"},{"key":"e_1_3_3_33_1","doi-asserted-by":"publisher","DOI":"10.1029\/2004JA010888"},{"key":"e_1_3_3_34_1","doi-asserted-by":"publisher","DOI":"10.5194\/acp-11-6153-2011"},{"key":"e_1_3_3_35_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2006.0127"},{"key":"e_1_3_3_36_1","first-page":"3193","volume-title":"In 27th International Cosmic Ray Conference, under the auspices of the International Union of Pure and Applied Physics","author":"Kuznetsov N.V.","year":"2001","unstructured":"Kuznetsov N.V., , Nymmik R.A., , Panasyuk M.I. 2001. The balance between fluxes of galactic cosmic rays and solar energetic particles, depending on solar activity. In 27th International Cosmic Ray Conference, under the auspices of the International Union of Pure and Applied Physics, 3193."},{"key":"e_1_3_3_37_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.asr.2004.09.021"},{"key":"e_1_3_3_38_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2006.0128"},{"key":"e_1_3_3_39_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11214-008-9413-5"},{"key":"e_1_3_3_40_1","doi-asserted-by":"publisher","DOI":"10.1029\/1999JA000373"},{"key":"e_1_3_3_41_1","doi-asserted-by":"publisher","DOI":"10.1086\/508982"},{"key":"e_1_3_3_42_1","doi-asserted-by":"publisher","DOI":"10.1086\/192295"},{"key":"e_1_3_3_43_1","doi-asserted-by":"publisher","DOI":"10.1175\/1520-0469(1967)024<0241:TEOTAW>2.0.CO;2"},{"key":"e_1_3_3_44_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2010.0603"},{"key":"e_1_3_3_45_1","doi-asserted-by":"publisher","DOI":"10.1029\/2004RS003110"},{"key":"e_1_3_3_46_1","doi-asserted-by":"publisher","DOI":"10.1029\/97JD00237"},{"key":"e_1_3_3_47_1","doi-asserted-by":"publisher","DOI":"10.1016\/0032-0633(75)90104-X"},{"key":"e_1_3_3_48_1","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRevD.66.010001"},{"key":"e_1_3_3_49_1","doi-asserted-by":"publisher","DOI":"10.1016\/S1364-6826(96)00109-5"},{"key":"e_1_3_3_50_1","doi-asserted-by":"publisher","DOI":"10.1089\/153110702753621321"},{"key":"e_1_3_3_51_1","first-page":"187","article-title":"A spectroscopic survey of red dwarf flare stars","volume":"217","author":"Pettersen B.R.","year":"1989","unstructured":"Pettersen B.R., , Hawley S.L. 1989. A spectroscopic survey of red dwarf flare stars. Astron Astrophys, 217:187\u2013200.","journal-title":"Astron Astrophys"},{"key":"e_1_3_3_52_1","doi-asserted-by":"publisher","DOI":"10.1063\/1.432812"},{"key":"e_1_3_3_53_1","doi-asserted-by":"publisher","DOI":"10.1051\/0004-6361\/201014368"},{"key":"e_1_3_3_54_1","doi-asserted-by":"publisher","DOI":"10.1088\/0004-6256\/143\/4\/93"},{"key":"e_1_3_3_55_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jqsrt.2004.10.008"},{"key":"e_1_3_3_56_1","first-page":"441","volume-title":"Proceedings of the Solar Wind 11 \/ SOHO 16: Connecting Sun and Heliosphere, ESA SP-592","author":"Ruzmaikin A.","year":"2005","unstructured":"Ruzmaikin A., , Li G., , Zank G., , Feynman J., , Jun I. 2005. The radial dependence of solar energetic particle fluxes. Proceedings of the Solar Wind 11 \/ SOHO 16: Connecting Sun and Heliosphere, ESA SP-592 Fleck B., , Zurbuchen T.H., , Lacoste H. European Space Agency, Noordwijk the Netherlands, 441\u2013444."},{"key":"e_1_3_3_57_1","volume-title":"Chemical Kinetics and Photochemical Data for Use in Atmospheric Studies, Evaluation No. 14","author":"Sander S.P.","year":"2003","unstructured":"Sander S.P., , Finlayson-Pitts B.J., , Friedl R.R., , Golden D.M., , Huie R.E., , Kolb C.E., , Kurylo M.J., , Molina M.J., , Moortgat G.K., , Orkin V.L., , Ravishankara A.R. 2003. Chemical Kinetics and Photochemical Data for Use in Atmospheric Studies, Evaluation No. 14. Jet Propulsion Laboratory Publication 02-25, Jet Propulsion Laboratory: Pasadena, CA."},{"key":"e_1_3_3_58_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2006.0125"},{"key":"e_1_3_3_59_1","doi-asserted-by":"publisher","DOI":"10.1016\/S1364-6826(02)00078-0"},{"key":"e_1_3_3_60_1","first-page":"381","volume-title":"IRS 2000: Current Problems in Atmospheric Radiation","author":"Schreier F.","year":"2001","unstructured":"Schreier F., , Schimpf B. 2001. A new efficient line-by-line code for high resolution atmospheric radiation computations incl. derivatives. IRS 2000: Current Problems in Atmospheric Radiation. Smith W.L., , Timofeyev Y. A. Deepak Publishing: Hampton, VA, 381\u2013384."},{"key":"e_1_3_3_61_1","doi-asserted-by":"publisher","DOI":"10.1089\/153110703322736024"},{"key":"e_1_3_3_62_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2005.5.706"},{"key":"e_1_3_3_63_1","doi-asserted-by":"publisher","DOI":"10.1089\/ast.2009.0376"},{"key":"e_1_3_3_64_1","doi-asserted-by":"publisher","DOI":"10.1086\/170477"},{"key":"e_1_3_3_65_1","doi-asserted-by":"publisher","DOI":"10.1029\/2008JD010863"},{"key":"e_1_3_3_66_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0273-1177(02)00497-0"},{"key":"e_1_3_3_67_1","doi-asserted-by":"publisher","DOI":"10.1016\/S1364-6826(97)00001-1"},{"key":"e_1_3_3_68_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.1183445"},{"key":"e_1_3_3_69_1","doi-asserted-by":"publisher","DOI":"10.1086\/429799"},{"key":"e_1_3_3_70_1","doi-asserted-by":"publisher","DOI":"10.1086\/496914"},{"key":"e_1_3_3_71_1","doi-asserted-by":"publisher","DOI":"10.1016\/0032-0633(84)90074-6"},{"key":"e_1_3_3_72_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-4073(02)00262-5"},{"key":"e_1_3_3_73_1","doi-asserted-by":"publisher","DOI":"10.1029\/1999JD900403"},{"key":"e_1_3_3_74_1","volume-title":"Scientific Assessment of Ozone Depletion","author":"WMO","year":"1994","unstructured":"WMO. 1994. Scientific Assessment of Ozone DepletionReport Number 37World Meteorological Organization (WMO): Geneva, Switzerland."},{"key":"e_1_3_3_75_1","doi-asserted-by":"publisher","DOI":"10.1147\/rd.401.0019"}],"container-title":["Astrobiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1089\/ast.2011.0682","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1089\/ast.2011.0682","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1089\/ast.2011.0682","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T12:04:09Z","timestamp":1777377849000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1089\/ast.2011.0682"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,12]]},"references-count":74,"journal-issue":{"issue":"12","published-print":{"date-parts":[[2012,12]]}},"alternative-id":["10.1089\/ast.2011.0682"],"URL":"https:\/\/doi.org\/10.1089\/ast.2011.0682","relation":{},"ISSN":["1531-1074","1557-8070"],"issn-type":[{"value":"1531-1074","type":"print"},{"value":"1557-8070","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,12]]}}}