(r2) ZplusD11 < LHCb

LHCb Web>LHCbQEEPublicResults>ZplusD11 (revision 2) (raw view)~~EditAttachPDF~~

---+Observation of associated production of a Z boson with a D meson in the forward region

The paper is available [[http://arxiv.org/pdf/1401.3245.pdf][here]].

arXiv: 1401.3245 

---++  Abstract
A search for associated production of a Z boson with an open charm meson is presented using a data sample, corresponding to an integrated luminosity of 1.0 fb<sup>&#8722;1</sup> of proton–proton collisions at a centre-of-mass energy of 7 TeV, collected by the LHCb experiment. Seven candidate events for associated production of a Z boson with a D<sup>0</sup> meson and four candidate events for a Z boson with a D<sup>+</sup> meson are observed with a combined significance of 5.1 standard deviations. The production cross-sections in the forward region are measured to be

&#963;Z<sub>&#8594;&#956;+ &#956;&#8722;</sub>,D<sup>0</sup> = 2.50 ± 1.12 ± 0.22 pb

&#963;Z<sub>&#8594;&#956;+ &#956;&#8722;</sub>,D<sup>+</sup> = 0.44 ± 0.23 ± 0.03 pb,

where the first uncertainty is statistical and the second systematic.

---++  Figures
(pdf and eps versions are available under attachments).

%TABLE{ tableborder="0" cellpadding="4" cellspacing="3" cellborder="0" columnwidths="70%,30%" }%
| * Caption * | * Figure * |
|Figure 1: Invariant mass distribution for Z (left) and D (right) candidates for Z + D<sup>0</sup> (top) and Z + D<sup>+</sup> (bottom) events. The superimposed curves represent the projection of the fit described in Sect. 4.|<img src="%ATTACHURLPATH%/Fig1a.png" alt="Fig1a.png" width='283' height='192' /> |
|Figure 1 top right|<img src="%ATTACHURLPATH%/Fig1b.png" alt="Fig1b.png" width='283' height='192' /> |
|Figure 1 bottom left|<img src="%ATTACHURLPATH%/Fig1c.png" alt="Fig1c.png" width='283' height='192' /> |
|Figure 1 bottom right|<img src="%ATTACHURLPATH%/Fig1d.png" alt="Fig1d.png" width='283' height='192' /> |
|Figure 2: Invariant mass of the Z and D<sup>0</sup> (left) and Z and D<sup>+</sup> (right) candidates (shown as black dots) compared to the fit (see text) that was used to extract the combinatorial background. The fit shown includes the signal and the background components. The colour scale shows the PDF value at any given point. | <img src="%ATTACHURLPATH%/Fig2a.png" alt="Fig2a.png" width='283' /> <img src="%ATTACHURLPATH%/Fig2b.png" alt="Fig2b.png" width='283' height='192' /> |
|Supplementary: Graphical comparison to theory predictions. The D<sub>s</sub><sup>+</sup>and &#923;<sub>c</sub><sup>+</sup> states were searched for in the decay channels D<sub>s</sub> &#8594; &#966;(&#8594; K K )&#960; and &#923;<sub>c</sub> &#8594; pK &#960; with no observed candidates. The measured cross-section is expected to be the sum of SPS and DPS.| <img src="%ATTACHURLPATH%/Fig3.png" alt="Fig3.png" width='283' /> |

-- Main.KatharinaMueller - 15 Jan 2014

Attachments

Topic attachments
I	Attachment	History	Action	Size	Date	Who
eps	Fig1a.eps	r1	manage	8.5 K	2014-01-15 - 11:26	KatharinaMueller
pdf	Fig1a.pdf	r1	manage	14.3 K	2014-01-15 - 11:26	KatharinaMueller
png	Fig1a.png	r1	manage	10.5 K	2014-01-15 - 11:26	KatharinaMueller
eps	Fig1b.eps	r1	manage	8.0 K	2014-01-15 - 11:26	KatharinaMueller
pdf	Fig1b.pdf	r1	manage	14.1 K	2014-01-15 - 11:26	KatharinaMueller
png	Fig1b.png	r1	manage	10.4 K	2014-01-15 - 11:26	KatharinaMueller
eps	Fig1c.eps	r1	manage	8.6 K	2014-01-15 - 11:26	KatharinaMueller
png	Fig1c.png	r1	manage	10.4 K	2014-01-15 - 11:29	KatharinaMueller
eps	Fig1d.eps	r1	manage	8.4 K	2014-01-15 - 11:29	KatharinaMueller
pdf	Fig1d.pdf	r1	manage	14.1 K	2014-01-15 - 11:29	KatharinaMueller
png	Fig1d.png	r1	manage	10.2 K	2014-01-15 - 11:29	KatharinaMueller
eps	Fig2a.eps	r1	manage	467.8 K	2014-01-15 - 11:29	KatharinaMueller
pdf	Fig2a.pdf	r1	manage	126.0 K	2014-01-15 - 11:29	KatharinaMueller
png	Fig2a.png	r1	manage	36.2 K	2014-01-15 - 11:29	KatharinaMueller
eps	Fig2b.eps	r1	manage	467.3 K	2014-01-15 - 11:29	KatharinaMueller
pdf	Fig2b.pdf	r1	manage	128.9 K	2014-01-15 - 11:29	KatharinaMueller
png	Fig2b.png	r1	manage	35.1 K	2014-01-15 - 11:29	KatharinaMueller
eps	Fig3.eps	r1	manage	14.6 K	2014-01-15 - 11:31	KatharinaMueller
pdf	Fig3.pdf	r1	manage	15.3 K	2014-01-15 - 11:31	KatharinaMueller
png	Fig3.png	r1	manage	8.4 K	2014-01-15 - 11:31	KatharinaMueller

Topic revision: r2 - 2014-01-16 - KatharinaMueller

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