(r1) DetectorComponents < CMS

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---+ Detector structure and naming conventions

<p align="center">&emsp;&emsp; Barrel &emsp;&rarr;&emsp; Half Shell &emsp;&rarr;&emsp; Layer &emsp;&rarr;&emsp; Ladder &emsp;&rarr;&emsp; Module <br /> &uarr; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &darr;<br /> &emsp; Pixel &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;ROC <br />&emsp; &darr; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp; &uarr;†—<br /> &emsp;&emsp; Endcap &rarr; Half Cylinder &rarr; Half Disk &rarr; Blade &rarr; Panel &rarr; Module</p>

---+++++ Pixel detector

<br />The Pixel detector consists of a central barrel and two endcaps at both ends (?&lt;i&gt;z&lt;/i&gt;) of the barrel. Together, the endcaps are known as the forward Pixel or Pixel Endcap.

<p align="center"> </p>

<p align="center"><img alt="pixel.png" src="%ATTACHURL%/pixel.png" /> <br />Figure: Diagram of the Pixel detector.</p>

---++++++ Barrel

Physically, the barrel is separated vertically (&lt;i&gt;y&lt;/i&gt;-axis) to give two half-barrels. For the purpose of DAQ and DCS (but not for alignment), each half-barrel is considered to be made of two half-shells joined at &lt;i&gt;z&lt;/i&gt; = 0. Therefore, the Pixel Barrel consists of four half-shells denoted as !BmI, !BmO, !BpI, !BpO, where 'p' stands for "plus" (+&lt;i&gt;z&lt;/i&gt;), 'm' for "minus" (&minus;&lt;i&gt;z&lt;/i&gt;), 'I' for "Inner" (+&lt;i&gt;x&lt;/i&gt;), 'O' for "Outer" (&minus;&lt;i&gt;x&lt;/i&gt;).

<p align="center"><img alt="barrel.png" src="%ATTACHURL%/barrel.png" /> <br />Figure: Schematic of Pixel Barrel showing the half-shells.</p> <p align="center"><img alt="half-barrel.png" src="%ATTACHURL%/half-barrel.png" /> <img alt="half-barrel.jpg" src="%ATTACHURL%/half-barrel.jpg" /> <br />Figure: (Left) computer-aided drawing of a half-barrel in upright position. (Right) photograph of a half-barrel lying down.</p>

---++++++ Half shell

Each half-shell has 3 layers numbered as 1, 2, 3 in increasing radii. Logically, it is useful to divide each half-shell into 8 sectors in &lt;i&gt;&phi;&lt;/i&gt;, Sector1 to Sector8, where the numbering increases from top to bottom (see figure).
<p align="center"><img alt="sectors.png" src="%ATTACHURL%/sectors.png" /> <br />Figure: <em>r</em>-<em>&phi;</em> view of Pixel Barrel showing the sector numbers.</p>

---++++++ Layer

Layer1 (considering a semi-circular surface) has 10 (so-called) ladders arranged symmetrically in &lt;i&gt;&phi;&lt;/i&gt;, while Layer2 has 16 and Layer3 has 22. Due to the separation in &lt;i&gt;y&lt;/i&gt;, the top and bottom ladders are actually half-ladders, but most of the time, we will simply refer to all as ladders.
<p align="center"><img alt="layer1.png" src="%ATTACHURL%/layer1.png" /> <br />Figure: <em>r</em>-<em>&phi;</em> view of the first layers of Pixel Barrel (2 half-shells together) showing the arrangement of the ladders.</p> <p align="center"><img alt="layer1.jpg" src="%ATTACHURL%/layer1.jpg" /> <br />Figure: Photograph of Layer1 of a half-barrel.</p>

---++++++ Ladder

A ladder consists of 8 modules joined end to end along the length of the barrel, four on the -z side and four on the +z side. To be precise, sometimes the letter 'F' or 'H' is used to indicate a full- or half-ladder in a label.
---++++++ Module

<div id="_mcePaste">A module (or sensor) of the Pixel Barrel has either 8 or 16 readout chips (ROC) arranged in a 1 × 8 (for half-ladders) or 2 × 8 (for full-ladders) configuration.</div>

<p align="center"><img alt="module.png" src="%ATTACHURL%/module.png" /> <img alt="module.jpg" src="%ATTACHURL%/module.jpg" /> <br />Figure: (Left) computer-aided drawing of a 2 × 8 barrel module. (Right) photograph of a 2 × 8 barrel module.</p>

Readout chip (ROC)

The readout chip is an array of 80 × 52 pixels, each of size 100 &mu;m × 150 &mu;m.

<p align="center"><img alt="ROC.png" src="%ATTACHURL%/ROC.png" /> <img alt="ROC.jpg" src="%ATTACHURL%/ROC.jpg" /> <br />Figure: Computer-aided drawing (left) and photograph (right) of a ROC.</p>

-- Main.BalintRadics - 2011-03-02

Attachments

Topic attachments
I	Attachment	History	Action	Size	Date	Who
jpg	ROC.jpg	r1	manage	109.3 K	2011-03-02 - 22:25	BalintRadics
png	ROC.png	r1	manage	724.4 K	2011-03-02 - 22:24	BalintRadics
png	barrel.png	r1	manage	24.0 K	2011-03-02 - 21:41	BalintRadics
jpg	half-barrel.jpg	r1	manage	45.5 K	2011-03-02 - 21:43	BalintRadics
png	half-barrel.png	r1	manage	386.0 K	2011-03-02 - 21:42	BalintRadics
jpg	layer1.jpg	r1	manage	206.4 K	2011-03-02 - 22:21	BalintRadics
png	layer1.png	r1	manage	7.1 K	2011-03-02 - 22:20	BalintRadics
jpg	module.jpg	r1	manage	41.0 K	2011-03-02 - 22:24	BalintRadics
png	module.png	r1	manage	281.0 K	2011-03-02 - 22:24	BalintRadics
png	pixel.png	r1	manage	207.6 K	2011-03-02 - 21:35	BalintRadics
png	sectors.png	r1	manage	133.5 K	2011-03-02 - 22:18	BalintRadics

Topic revision: r1 - 2011-03-02 - BalintRadics

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