Search for double-beta decay of <sup>136</sup>Xe to excited states of <sup>136</sup>Ba with the KamLAND-Zen experiment

文摘

A search for double-beta decays of p>136p>Xe to excited states of p>136p>Ba has been performed with the first phase data set of the KamLAND-Zen experiment. The pan id="mmlsi1" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si1.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=3e8d6adf32ae6893e5a1f420ed8ca958">mg class="imgLazyJSB inlineImage" height="19" width="20" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si1.gif">pt>mg height="19" border="0" style="vertical-align:bottom" width="20" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si1.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si1.gif" overflow="scroll"><msubsup><mrow><mn>0mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup>math>pan>pan>pan>, pan id="mmlsi2" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si2.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=5b97f0f3fafd4b39f6e23bbc7130e681">mg class="imgLazyJSB inlineImage" height="19" width="20" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si2.gif">pt>mg height="19" border="0" style="vertical-align:bottom" width="20" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si2.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si2.gif" overflow="scroll"><msubsup><mrow><mn>2mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup>math>pan>pan>pan> and pan id="mmlsi3" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si3.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=6a73bef336671d668075caec9f321760">mg class="imgLazyJSB inlineImage" height="19" width="20" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si3.gif">pt>mg height="19" border="0" style="vertical-align:bottom" width="20" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si3.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si3.gif" overflow="scroll"><msubsup><mrow><mn>2mn>mrow><mrow><mn>2mn>mrow><mrow><mo>+mo>mrow>msubsup>math>pan>pan>pan> transitions of pan id="mmlsi4" class="mathmlsrc">pan class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si4.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=c34b03801f7ec0e33a08a1f178821773" title="Click to view the MathML source">0νββpan>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si4.gif" overflow="scroll"><mn>0mn><mi>νmi><mi>βmi><mi>βmi>math>pan>pan>pan> decay were evaluated in an exposure of pan id="mmlsi30" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si30.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=5c1df6e57827ed2dd26b0eb128d9b4a8">mg class="imgLazyJSB inlineImage" height="15" width="73" alt="View the MathML source" style="margin-top: -5px; vertical-align: middle" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si30.gif">pt>mg height="15" border="0" style="vertical-align:bottom" width="73" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si30.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si30.gif" overflow="scroll"><mn>89.5mn><mtext> mtext><mtext>kgmtext><mspace width="0.2em">mspace><mo>⋅mo><mspace width="0.2em">mspace><mtext>yrmtext>math>pan>pan>pan> of p>136p>Xe, while the same transitions of pan id="mmlsi6" class="mathmlsrc">pan class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si6.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=8574a6a94c3e4ca037946834f4fa28bc" title="Click to view the MathML source">2νββpan>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si6.gif" overflow="scroll"><mn>2mn><mi>νmi><mi>βmi><mi>βmi>math>pan>pan>pan> decay were evaluated in an exposure of pan id="mmlsi7" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si7.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=0e05e261d4e72ae276048dd21e7785bc">mg class="imgLazyJSB inlineImage" height="14" width="73" alt="View the MathML source" style="margin-top: -5px; vertical-align: middle" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si7.gif">pt>mg height="14" border="0" style="vertical-align:bottom" width="73" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si7.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si7.gif" overflow="scroll"><mn>61.8mn><mtext> mtext><mtext>kgmtext><mspace width="0.2em">mspace><mo>⋅mo><mspace width="0.2em">mspace><mtext>yrmtext>math>pan>pan>pan>. No excess over background was found for all decay modes. The lower half-life limits of the pan id="mmlsi2" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si2.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=5b97f0f3fafd4b39f6e23bbc7130e681">mg class="imgLazyJSB inlineImage" height="19" width="20" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si2.gif">pt>mg height="19" border="0" style="vertical-align:bottom" width="20" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si2.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si2.gif" overflow="scroll"><msubsup><mrow><mn>2mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup>math>pan>pan>pan> state transitions of pan id="mmlsi4" class="mathmlsrc">pan class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si4.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=c34b03801f7ec0e33a08a1f178821773" title="Click to view the MathML source">0νββpan>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si4.gif" overflow="scroll"><mn>0mn><mi>νmi><mi>βmi><mi>βmi>math>pan>pan>pan> and pan id="mmlsi6" class="mathmlsrc">pan class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si6.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=8574a6a94c3e4ca037946834f4fa28bc" title="Click to view the MathML source">2νββpan>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si6.gif" overflow="scroll"><mn>2mn><mi>νmi><mi>βmi><mi>βmi>math>pan>pan>pan> decay were improved to pan id="mmlsi8" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si8.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=b4628e9c36c110e1d9be96e29619f686">mg class="imgLazyJSB inlineImage" height="23" width="207" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si8.gif">pt>mg height="23" border="0" style="vertical-align:bottom" width="207" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si8.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si8.gif" overflow="scroll"><msubsup><mrow><mi>Tmi>mrow><mrow><mn>1mn><mo stretchy="false">/mo><mn>2mn>mrow><mrow><mn>0mn><mi>νmi>mrow>msubsup><mo stretchy="false">(mo><msup><mrow><mn>0mn>mrow><mrow><mo>+mo>mrow>msup><mo stretchy="false">→mo><msubsup><mrow><mn>2mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup><mo stretchy="false">)mo><mo>>mo><mn>2.6mn><mo>×mo><msup><mrow><mn>10mn>mrow><mrow><mn>25mn>mrow>msup><mtext> mtext><mtext>yrmtext>math>pan>pan>pan> and pan id="mmlsi9" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si9.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=541315f08115814b9a20f573d91a9a21">mg class="imgLazyJSB inlineImage" height="23" width="207" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si9.gif">pt>mg height="23" border="0" style="vertical-align:bottom" width="207" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si9.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si9.gif" overflow="scroll"><msubsup><mrow><mi>Tmi>mrow><mrow><mn>1mn><mo stretchy="false">/mo><mn>2mn>mrow><mrow><mn>2mn><mi>νmi>mrow>msubsup><mo stretchy="false">(mo><msup><mrow><mn>0mn>mrow><mrow><mo>+mo>mrow>msup><mo stretchy="false">→mo><msubsup><mrow><mn>2mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup><mo stretchy="false">)mo><mo>>mo><mn>4.6mn><mo>×mo><msup><mrow><mn>10mn>mrow><mrow><mn>23mn>mrow>msup><mtext> mtext><mtext>yrmtext>math>pan>pan>pan> (90% C.L.), respectively. We report on the first experimental lower half-life limits for the transitions to the pan id="mmlsi1" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si1.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=3e8d6adf32ae6893e5a1f420ed8ca958">mg class="imgLazyJSB inlineImage" height="19" width="20" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si1.gif">pt>mg height="19" border="0" style="vertical-align:bottom" width="20" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si1.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si1.gif" overflow="scroll"><msubsup><mrow><mn>0mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup>math>pan>pan>pan> state of p>136p>Xe for pan id="mmlsi4" class="mathmlsrc">pan class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si4.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=c34b03801f7ec0e33a08a1f178821773" title="Click to view the MathML source">0νββpan>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si4.gif" overflow="scroll"><mn>0mn><mi>νmi><mi>βmi><mi>βmi>math>pan>pan>pan> and pan id="mmlsi6" class="mathmlsrc">pan class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si6.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=8574a6a94c3e4ca037946834f4fa28bc" title="Click to view the MathML source">2νββpan>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si6.gif" overflow="scroll"><mn>2mn><mi>νmi><mi>βmi><mi>βmi>math>pan>pan>pan> decay. They are pan id="mmlsi10" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si10.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=efcf6db719ddb553bb9b9bf3dd9da351">mg class="imgLazyJSB inlineImage" height="23" width="207" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si10.gif">pt>mg height="23" border="0" style="vertical-align:bottom" width="207" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si10.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si10.gif" overflow="scroll"><msubsup><mrow><mi>Tmi>mrow><mrow><mn>1mn><mo stretchy="false">/mo><mn>2mn>mrow><mrow><mn>0mn><mi>νmi>mrow>msubsup><mo stretchy="false">(mo><msup><mrow><mn>0mn>mrow><mrow><mo>+mo>mrow>msup><mo stretchy="false">→mo><msubsup><mrow><mn>0mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup><mo stretchy="false">)mo><mo>>mo><mn>2.4mn><mo>×mo><msup><mrow><mn>10mn>mrow><mrow><mn>25mn>mrow>msup><mtext> mtext><mtext>yrmtext>math>pan>pan>pan> and pan id="mmlsi11" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si11.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=1fbdfb4dc5e17b92608c9c4257c54408">mg class="imgLazyJSB inlineImage" height="23" width="207" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si11.gif">pt>mg height="23" border="0" style="vertical-align:bottom" width="207" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si11.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si11.gif" overflow="scroll"><msubsup><mrow><mi>Tmi>mrow><mrow><mn>1mn><mo stretchy="false">/mo><mn>2mn>mrow><mrow><mn>2mn><mi>νmi>mrow>msubsup><mo stretchy="false">(mo><msup><mrow><mn>0mn>mrow><mrow><mo>+mo>mrow>msup><mo stretchy="false">→mo><msubsup><mrow><mn>0mn>mrow><mrow><mn>1mn>mrow><mrow><mo>+mo>mrow>msubsup><mo stretchy="false">)mo><mo>>mo><mn>8.3mn><mo>×mo><msup><mrow><mn>10mn>mrow><mrow><mn>23mn>mrow>msup><mtext> mtext><mtext>yrmtext>math>pan>pan>pan> (90% C.L.). The transitions to the pan id="mmlsi3" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si3.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=6a73bef336671d668075caec9f321760">mg class="imgLazyJSB inlineImage" height="19" width="20" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si3.gif">pt>mg height="19" border="0" style="vertical-align:bottom" width="20" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si3.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si3.gif" overflow="scroll"><msubsup><mrow><mn>2mn>mrow><mrow><mn>2mn>mrow><mrow><mo>+mo>mrow>msubsup>math>pan>pan>pan> states are also evaluated for the first time to be pan id="mmlsi12" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si12.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=a9ff1e7c94aed29982a846cb279bcc0d">mg class="imgLazyJSB inlineImage" height="23" width="207" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si12.gif">pt>mg height="23" border="0" style="vertical-align:bottom" width="207" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si12.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si12.gif" overflow="scroll"><msubsup><mrow><mi>Tmi>mrow><mrow><mn>1mn><mo stretchy="false">/mo><mn>2mn>mrow><mrow><mn>0mn><mi>νmi>mrow>msubsup><mo stretchy="false">(mo><msup><mrow><mn>0mn>mrow><mrow><mo>+mo>mrow>msup><mo stretchy="false">→mo><msubsup><mrow><mn>2mn>mrow><mrow><mn>2mn>mrow><mrow><mo>+mo>mrow>msubsup><mo stretchy="false">)mo><mo>>mo><mn>2.6mn><mo>×mo><msup><mrow><mn>10mn>mrow><mrow><mn>25mn>mrow>msup><mtext> mtext><mtext>yrmtext>math>pan>pan>pan> and pan id="mmlsi13" class="mathmlsrc">mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S037594741500278X&_mathId=si13.gif&_user=111111111&_pii=S037594741500278X&_rdoc=1&_issn=03759474&md5=c5eaebf4982e5ae29f08c69c415c182d">mg class="imgLazyJSB inlineImage" height="23" width="207" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S037594741500278X-si13.gif">pt>mg height="23" border="0" style="vertical-align:bottom" width="207" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S037594741500278X-si13.gif">pt>pan class="mathContainer hidden">pan class="mathCode"><math altimg="si13.gif" overflow="scroll"><msubsup><mrow><mi>Tmi>mrow><mrow><mn>1mn><mo stretchy="false">/mo><mn>2mn>mrow><mrow><mn>2mn><mi>νmi>mrow>msubsup><mo stretchy="false">(mo><msup><mrow><mn>0mn>mrow><mrow><mo>+mo>mrow>msup><mo stretchy="false">→mo><msubsup><mrow><mn>2mn>mrow><mrow><mn>2mn>mrow><mrow><mo>+mo>mrow>msubsup><mo stretchy="false">)mo><mo>>mo><mn>9.0mn><mo>×mo><msup><mrow><mn>10mn>mrow><mrow><mn>23mn>mrow>msup><mtext> mtext><mtext>yrmtext>math>pan>pan>pan> (90% C.L.). These results are compared to recent theoretical predictions.