1 / 4

Status of SPD Preprocessor Class Paul Nilsson

Status of SPD Preprocessor Class Paul Nilsson. AliITSPreprocessorSPD Status. Noisy channel finder implemented in new AliITSPreprocessorSPD class Two versions of the algorithm Optimized for data (noisy channels mixed with real hits)

dylan-barry
Download Presentation

Status of SPD Preprocessor Class Paul Nilsson

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Status of SPD Preprocessor Class Paul Nilsson

  2. AliITSPreprocessorSPD Status Noisy channel finder implemented in new AliITSPreprocessorSPD class • Two versions of the algorithm • Optimized for data (noisy channels mixed with real hits) • Optimized for calibration data (i.e. data taken without beam) • Both versions scan the 2D histograms containing the digits (one histogram per SPD module) • Algorithm 1 compares each bin with the surrounding channels (if the bin content > n times the average neighborhood, it is considered “noisy”) • Algorithm 2 assumes only noisy channels present (everything above a threshold is per definition “noisy”) • Identified noisy channels are so far only stored in a tree (work in progress) P. Nilsson

  3. AliITSPreprocessorSPD Status // Example of how to run the preprocessor for the SPD { // Instantiate the preprocessor AliITSPreprocessorSPD prepSPD("run_its_189_5k.root"); // Select a geometry (either kALICEGeometry or kTestBeamGeometry) prepSPD.SetGeometryMode(AliITSPreprocessorSPD::kTestBeamGeometry); // Select the noisy channel finder algorithm (either kOptimizedForRealData or // kOptimizedForCalibrationData, real data is default) prepSPD.SelectAlgorithm(AliITSPreprocessorSPD::kOptimizedForRealData); // Set the minimum number of times a channel must have fired to be called noisy (default is 10.) prepSPD.SetThreshold(20.); // Set the current bin content to average neighborhood ratio (default is 5.) prepSPD.SetThresholdRatio(5.); // Set the number of events (default is all available events) prepSPD.SetMaximumNumberOfEvents(5000); // Find the noisy channels prepSPD.FindNoisyChannels(); // Print out the found noisy channels (dump to standard output) prepSPD.PrintNoisyChannels(); // Remove the found noisy channels prepSPD.RemoveNoisyChannels(); } A noisy channel has to fire at least 20 times, 5 times the average of the neighbors P. Nilsson

  4. AliITSPreprocessorSPD Status Data taken last week Test Beam 2004 data – Hits in SPD module 1 Not real maximum Row Row Column Column Raw data before noisy channel removal After noisy channel removal P. Nilsson

More Related