Combine the arugula, celery, carrot, scallions, garlic and tarragon in a food processor and pulse until very finely chopped.
Add the sour cream, mayonnaise and cream cheese and pulse to combine. Add the crushed chips and pulse a few more times until smooth. Season with salt and pepper.
Transfer to a bowl and chill 30 minutes or up to 8 hours. Serve with your favorite vegetables.